Gather your materials. You will need a hose long enough to span from where the liquid is to where you want the liquid to go. You will also need a water source, like a sink.
Put one end of the siphon hose into the water you want to get rid of (lets say you are taking the water out of a fish tank). The hose must be submerged in the water. Put the other end of the hose where you want the water to go (lets say a sink). The place where you want the water to go must be lower than the place where the water currently is.
Take the end of the siphon hose that is where you want the water to go (the sink) and continually fill it with water (from the sink faucet) until the water goes through to the other end (the fish tank). Once the water starts coming out the other end (into the fish tank), quickly move the siphon hose from the water (sink faucet) and put it into the sink to drain.