Sometimes I just stand at arm's length and lean over an stare for a bit. The bees in such cases are too busy to bother with you (and indeed I've used this exercise as exposure therapy for myself and two kids who were all previously nervous around bees) and seeing three or four species in a five minute span, you can start to tell them apart in a way you won't get if you spread that duration out over a month.

Lavender and rosemary are very good stages in this regard, roses and the whole rose family (including blackberries, apples, cherries) are also good. If you're on the west coast the ceanothus bush is pollinator paradise.