If your celebrating'dry Holi', just smear colors on each other. If it is full-fledged 'wet Holi', dissolve the colors in a bucket of water, use water guns(pichkaris) and shoot the colored water at each other.
Holi is the meaning of unity. No matter from which religion or which language you speak, you are as colorful and as joyful as others. In the day of holi everyone spread colors to other, and it signifies that everyone is same and color doesn't care about religions.
