No need for too many details, just look at this:



This is a good setup for residents whose only use is to produce energy or laze around in your base taking up space but you need their decent hobbies and work to increase certain skills/resources of your base.

If you are having difficulty getting a "helmet" which is part of the recipe for training dummies, you can craft buckets at a Carpenter's Table. They serve as cheap helmets.

You may also be wondering, why training dummies instead of walls?
Well, you can have other uses for theses. For example, I am using this child resident to also farm handfuls of snow while I fish beside him (there's a water source that is cropped from the image). Also, while in that state, they can train their corresponding attack skills while you are active as any attempt for them to "escape" is instead registered as them attacking the dummies. A win-win situation.