Water resistant SPF 45 sunscreen, $21 by Jack Black
SPF (the sun protection factor) is a rating indicating how long you can be in the sun before burning. So if after 10 minutes you start feeling the burn, an SPF 15 will protect you for 150 minutes.
Side pockets can add extra bulk and will often balloon up with excess water and air.
Avoid elastic waistbands which pinch soft stomachs. Your drawstring should be tied comfortably at the hips, yet tight enough to stay put with a tug.
Darker colors and vertical stripes along the sides make for a long, leaner appearance.
Don't hide behind long shorts—the leg opening should hit a few inches above your knee.