Choose the kind of texture compound you want to work with. Select multipurpose joint compound for a ready-made compound or a texture compound powder that you have to mix together. Use a drill with an attached beater designed for drywall plaster to mix the powder compound.
Put a small amount of compound into your plastic bucket or pan. Add a small amount of measured water to the compound and stir together. Use a small amount of the mixture to try on your practice surface and decide if it is the effect you want. Add small amounts of water and stir together until you get the consistency you want.
Add sand to your compound if you want an old plaster-like effect. Use either 30 or 70 mesh for a smaller sharp white quartz sand. Add small, measured amounts of sand to your compound and stir together until you get the consistency you want.
Add optional color to the texture compound by adding the tinting powder to the water first, then mixing it with the powder texture compound. Use small, measured amounts of water and the tinting material to find the exact proportions you want.
Practice your texture technique on cardboard or spare drywall scraps. Apply the compound with different tools, from rollers to knives, and with different strokes, until deciding on the style you like. Move to the wall or ceiling to begin applying the compound.