Il buvait à même la bouteille = He was drinking out of the bottle itself.

[This is an inversion for à la bouteille même. Boire à même is not usually used of cups or glasses, but of bottles, jugs, streams, etc. For it implies that the containing vessel itself is being used to drink out of, and not any smaller vessel. Thus boire à même le verre would suggest that a spoon or smaller receptacle was not used.]

Il est à même de vous comprendre = He is able to understand you.

Cela revient au même = That comes to the same thing.

C'est cela même = That is the very thing.

Faites de même = Do the same.