People enjoy the intermission . Don't make it too short. You will find you are building community, and this is when most products are sold. Announce your next concert. Have a mailing list for signing.
Scares hell out of some performers.
However, depending on your room you may want a small amp. Oh, tell folks where the restroom is. Use what chairs you have, cushions and the floor. We have 80 folding director's chairs, which is helpful, and using an outbuilding means we don't have to rearrange furniture every few weeks. Look after your performer.