I remember that there was a way to say "do as you please" and it was something like "do as you thou".
The last word was something like tho/though. I just remember that it started with "th". Can anyone suggest a phrase that might fit this?
Maybe you are remembering
Do what thou wilt shall be the whole of the Law
LINK attributed to Aleister Crowley
There's "Do as you feel", which starts with an "f" rather than a "th". But then I tend to pronounce them the same anyway. It gets 3.8m hits on google.
Alternatively, slightly different is "Do whatever you feel". 1.6m hits on google, many of which are actually "Do whatever you feel like". Though of course it was used without the "like" in the Village People hit Y.M.C.A. Probably because it rhymed with "have a good meal".