I'll assume you are not a 2 week new guy and on that note...
Try just one session like this and see what you think.
If you have a very limited timeframe, arouse yourself somewhat and then douse your cock with some baby powder. Do 5 to 10 uli's with your right hand then immediately switch to your left hand. Keep rotating back and forth until you've done 5 sets with each hand.
The key to this is squeezing the snot out of your cock. Sqeeze hard. Expect red dots and a very noticeable temporary size increase in girth.
Do this routine daily, preferrably twice per day.