Sorry if this is a commonly asked question, but how do you know what smaller tiles to use when building a map?

I've started getting some expansions now, and I'm worried that since the smaller tiles aren't numbered, they may become difficult to manage.

I'm not sure I understand your question. All tiles needed are pictured in the quest setup.

If you're worried about mixing up the pieces, as far as non-numbered tiles, there are only a few different types:

1x2 extenders

1x2 ends

2x2 extensions (usually flip from A to B)

entrances and exits

The artwork on these tiles pretty clearly keeps them from being mixed up. That is, there are "classic" woods/castle like in the base game, Nerekhall city/black realm, Mists swamp/indoor, and Manor woods/manor. All of these look distinct.

Did you mean something else?

Hmm, okay.

Yeah, I guess I'm just used to all tiles being numbered in IA. It's probably not too big of a deal, I'll just have to try a different storage solution with this game. Thanks!