Wait until you reach the point where your penile tissues reached optimal expansion at 50%. You will be scared out of your mind that your penis suddenly grows twice as large after the session. This is not accounting for fluid retention either. It's pure internal expansion. This is where your body agrees to be malleable to accomodate the possible growth potential. My wife was scared out of her mind looking at a 7.5in girth monster after an intense 2.5 hours of length and girth routines. We tried to get my penis inside her, lubed up with her natural fluid and any lubricant we could, but she simply screamed in pure painful bliss. She forbid me exceeding 6.3in for her constant pleasures. 6.5in was her upper limit.