Don't use condoms that have expired. Before use, check the condom has not discoloured or become brittle. Find the right size. A condom that's too small can break, a condom that's too big can fall off.
Lubricant reduces the risk of the condom breaking.
Use water based lubricant such as Wetstuff or KY jelly. DO NOT use oil based products such as baby oil or Vaseline as they weaken the rubber leading to breakage. Store condoms in a cool dark place, even in the fridge if you live or travel in a hot climate. DO NOT store condoms in the car. Condoms should not be kept for any length of time in a wallet, purse or handbag.