Just by wearing the proper underwear will give your package the appearance of being MAS GRANDE. The trunk is by far your best option for package presentation because of the proportion and the shorter length of the legs.The second best option is the brief because they're supper supportive and are also great at giving the backside a little lift as well
Another important factor is color. Any lighter color will help. Darker colors will do you no favors if you're trying to enhance the appearance of your junk.
When the underwear comes off and you still want the appearance of being larger than your are I have one solution. MANSCAPE!!!! If you have a massive bush everything else is going to appear smaller.