Protect your eyes against possible breaking glass, chemicals, etc. by wearing safety glasses. Wear close-fitting clothes so that they don't catch on things and knock them over (sleeves, etc) or catch on fire. Tie your hair back so that it doesn't catch on fire or fall into chemical solutions. Natural fibers tend to be more flammable than man-made.
Consider what would happen if you shake a test tube that has chemicals in it. Consider what could happen if you look into a test tube where a chemical reaction is taking place. Consider what could happen if chemicals spill from the test tube while you are holding it.
Hope it helped : )