Currently fish in a largely weeded pond for bass. Where do I cast to get big bass? 

I'd toss a frog or a popping frog in the morning. After that'd I'd switch to a punching rig and target structure or anything else unusual. Depending on how weedy it is you might be able to get away with a heavier drop shot as well (eg. 3/8 ounce cylinder weight and a weedless worm on a medium or medium heavy setup with thicker line).

Topwater is your friend in thick vegetation.  Weightless plastics and very heavy weights can help with presenting the bait in ways that are more likely to get bit.

 

I'd try a floating worm 😎😎😎 

 

Where do you cast?:  holes in the grass or more sparse areas.  Near main lake structure (points/flats/cuts/ditches) and this time of year I'd be paralleling the bank every few casts just to keep em honest.