How to Rosin Your Bow?

Here is the usage method of Rosin:

Hold the rosin with your index finger and thumb, and thus tighten up the bow, evenly smear the rosin on the bowstring up and down. Suggested use: before smearing, rip a trace on rosin to make it powdery for quick and even smearing. Try to keep your hands away from rosin or pad with a tissue while smearing; otherwise it will become too sticky to clean.

If it still can not work, please see the video below.