in that guide you will learn various advanced tricks and strats that you can use in Challenges while trying to get Gold-medals in all categories; some of those tricks allow you to skip the whole Challenge or major part of it (saving you tons of time, steps & portals)

this guide is not about speedrunning the game (however you may speedrun the game with tricks you will learn here) and accent of the guide is on using various in-game glitches and advanced mechanics in beating Challenges

OoB (out of bounds) glitches are omitted on purpose

portal-bumping is the most basic trick that you can utilize in Portal Challenges. it allows to create (bump) portals in the places where you originally not supposed to (for example, behind walls or glasses), and therefore skip some parts of Challenges, or decrease the number of used portals, steps and time

• find a solid surface and put, say, a blue portal on it

• then shoot an orange portal at it, and see that game auto-corrected its placement and put it nearby a blue portal

• by moving cursor slightly at the left/right from a blue's portal center you will be able to create an orange portal on desired side

consider one thing - the first portal must stay perpendicularly to you position. if you cannot create (bump) a second portal, then most likely the first portal is put at certain angle. try to align yourself across the wall and shoot straight forward, make sure that you don't put portals at certain angle

some practical examples,

portal-bumping allows you to skip the half of the level, presumingly saving you lots of steps and time; there is a glass-wall that you can portal-bump ahead with a cube
in that chamber portal-bumping is especially useful. you can utilize the first portal-bumping to skip behind the closed door in the beginning (before GLaDOS have opened it for you), which allows you to save quite a lot of time...
...and the second portal-bumping might be used to get behind the glass-wall right above three turrets in the final room
a minor portal-bump can be created near the very first wall. it might be not that useful for most players, but still an interesting trick

wallclimbing is advanced trick that allows you to climb toward the wall with the help of any prop - cube, security camera, chair, etc.

• grab any prop, say a cube, move it close to the wall and jump on it

• move a crosshair downward at a 45 degree angle, and hold the crouch button

• grab the prop, jump, grab it again, jump again and continue doing it as fast as you can. basically, just repeatedly press "E" and "SPACE" button, while holding "CTRL"

to make it easier, bind jumping to the mousewheel and scroll it for faster jumping (using mousewheel is way faster than using "SPACE" button). use the following commands in the console

if you are using AutoHotKey, the you can utilize the following script. by holding "C" button you will repeatedly pressing "E" and "SPACE" buttons:

code from: https://wiki.sourceruns.org/wiki/AutoHotkey/Scripts

few practical examples,

you can use a cube here to wallclimb to the final area without raising any of lifts
you can use a security camera to wallclimb across the energo-field without using portals

save-button-glitch is advanced/intermediate strat that allows you to activate buttons and keep them in toggled state permanently. that trick requires timing and might not be a best trick for casual players, but still nice to know about it

• grab a cube and place it on the button, don't release the cube

• move cube from the button, but in the exact frame when button is losing a cube you need to quick-save the game (F6)

• quick-load the game (F9). if your timing was perfect then you will hold a cube in your arms, it will not press the button, while button itself (and related door) will be in toggled state (until you press the button again). for me it is easier to do that trick while crouching

few practical examples,

in that Chamber you can use a save-button glitch to press all three buttons on the floor, which might be useful to save few portals
here you can use a save-button glitch to permanently toggle a button near the end of the level, potentially saving yourself few steps because you don't need to return back for the cube

peek-a-portal is basic trick that allows you to shoot a portal through other portals without actual moving one of them

among all Challenges the only Chamber where that trick is useful is Chamber 15

• place a blue portal on the wall where you cannot get to

• place an orange portal close to you

• accurately peek thought orange portal and shoot a blue portal on the next wall where you cannot get to

• quickly dash back into the orange portal before new blue portal is created and proceed forward

advanced route with only two portals used, but requires more skills and good crouch-jumping

• place a blue portal on the wall very close to the water

• jump into the water and quickly create an orange portal on next wall and dash into the blue portal

• peek through blue portal and crouch-jump to the the lift

edge-glitch is advanced strat that glitches the game into thinking that you located into a different positing and allows you to either skip parts of the levels or create portals from the impossible position

among all Challenges the only chamber where that trick useful is Chamber 18

• get to that second platform and create a blue portal in that precise spot

• create an orange portal on the edge of platform here (again, be very precise)

• step on the orange portal from the above and crouch. if done right you should "stuck"

• now launch a blue portal in the spot here. you shall ended up near the end-level elevator. if you ended up in outbounds, then try to shoot a bit above/below/left/right - the exact location depends on how you placed both portals

• if you cannot do that trick, then, most probably, you have placed portals incorrectly, mind where exactly you need to place both portals to make that trick to work

if you wonder how the hell that glitch works, then maybe that picture will explain it better

image from: https://wiki.sourceruns.org/wiki/File:PortalEdgeGlitchExplained.png

flinging is the basic trick that game teaches you during the game. there is some spots in the Challenges where using of flinging is not obvious

• you can get that cube without activating the lift

• place a blue portal on the ceiling, and place an orange portal on the floor close to the lift

• jump into the orange portal and create a blue portal on the floor

• land on the lift and grab a cube

alternative way in two portals only, plus a better position of a second portal

• place a blue portal on the wall in position close to upper button, here

• place an orange portal in that position on the floor

• walk into the orange portal and jump into it from the higher platform (crouch during the flight)

• land on the lift and grab a cube

• place a blue portal on the ceiling, and place an orange portal on the floor close to the lift

• jump into the orange portal and create a blue portal on the floor

• land on the lift and exit

alternative way in two portals only, but takes a bit more time

• place an orange portal on the floor close to the lift (like in the method above)

• go up the stairs and wait until until they disappear

• create a blue portal on the floor and jump into it

• place an orange portal on the floor close to the final lift

• place a blue portal on the floor close to your position

• jump into the blue portal and land on the final lift

various miscellaneous tricks and strats that might be useful or just amusing

• with good jump and timing you can grab that cube without any portals

• you need to move toward that cube and jump from the button in about that spot

• then just grab the cube in the air and bring it down

• use a portal to rid the camera off the wall

• wait until an energo-ball will pass and jump-and-throw a camera into it

• depending on your luck and ricochet-factor and will land an energo-ball into the goal-station

• get to the right lift and jump toward closed door. there is a small gap on which you can land

• from there crouch-jump to the final-lift. the jump if very hard and require lots of efforts but doable

• grab the cube in the first room without using the portals

• use save-button-glitch to make the button stuck

• use wallclimbing to get with cube on the ledge

• use wallclimbing in the next room to get cube to the upper button

• use save-button-glitch to make that button stuck

• jump to next button with the cube and use save-button-glitch again to make it stuck too

• proceed to the exit

• use portal-bumping to get across the first wall

• get the security camera off the wall and use it to bounce energo-ball into the base

• use the same security camera you used before to wallclimb across the second wall

• use advanced peek-a-portal to pass thought next corridor in 2 portals

• use a crouch-jump to get the final-lift

if you want to thank me...

...then check my guide about fixing various game issues: launching, crashing, optimization, stuttering, gamepads, etc. the guide is huge, but the topic is broad to begin with
https://steamproxy-script.pipiskins.com/sharedfiles/filedetails/?id=1935376439