Find an old bottle..
...On the beach, rub it, and hope a genie comes out.
In all seriousness, we are doctors, not magicians. A strong oral steroid like Prednisone
can be used to temporarily clear your skin in a short period of time, but steroids
are powerful drugs and should not be taken for cosmetic reasons unless absolutely necessary. A much wiser plan is to plan further ahead and get on a sensible longterm regimen.