Repairing your base and decay

I’m trying to repair my base but I jus’t don’t know how to do it.

I googled it and watched some videos, but when I follow the instructions nothing happens.

I’m playing on an unmodded community sever.

You put the item in your slot. Lets say your repairing your metal door. Put it in whatever slot lets say 5. Go up to your door and click 5. If nothing happends its fully repaired.

Thanks, I’ll try it