I used to do the trying to look weak when I have it and vice versa thing but let it slip for a while and people still called and folded when I wanted them to for the most part. Most of the time when you're using certain sizings to own someone its because they're not very good and probably won't be paying attention to physical tells anyway.
v. important to have a balanced shaking range though. Get on an diet and exercise regime that'll have you weighing between 10 stone and 10 stone 5. Then you'll be skinny enough to be cold in almost every cardroom you'll find and you'll have a perfectly balanced shaking range.
i'm deadly serious btw.
I went with 10 stone + 10 stone 5 for a well balanced if overly aggro wobbling range