How Do I Pick My Favorite Fruit?

I love summertime for so many reasons but one in particular is that I go crazy buying fruit! It has been one of my cravings throughout my pregnancy.

This girl can polish off an entire watermelon in a matter of days, by myself. (And coincidentally, it looks like I've swallowed a watermelon too. lol) I've also been indulging in grapes, strawberries, bananas, oranges and as you can see from the picture, cantaloupe.  I've already told my friends and family, flowers are not necessary while I'm in the hospital having the baby, but an edible (fruit) arrangement is welcomed!

Either way, I need your help, I don't know how to pick two of my very favorites, cantaloupe or watermelon. What is the trick to knowing if it is good and sweet? I haven't had very good luck with either lately. Please share your 'picking methods.'