If you should get burned, treat it like any other burn, and of course if you should get some in your eyes or enough of a burn on your skin, see a doctor immediately. Glass containers are the best to show off the beauty of candle gel. A lot of the fun is shopping for unusual glasses to use, such as wine glasses, mugs etc. However, this certainly does not rule out using metal, clay or even seashells to hold your gel. The glass you select must be able to withstand a hot pour of candle gel.
Tempered glass is best.
You certainly don't want to take your glassware out of the freezer and pour into it. Pre-warming the glassware will help prevent stress on the glass as well as cut down on the amount of bubbles in the gel. In addition, you should select glassware that is stable and not easy to tip. The use of very narrow glassware should also be avoided. Besides potential blackening of the glass from candle combustion, a factor that is known as gel pool comes into play.