I would suggest that you avoid the canvas side until you are mastering the correct stropping movement and pressure. The leather side is enough to keep the blade sharp.
At the beginning I suggest that you keep extremely light pressure and compensate with more passes.
Personally I make 20 strops after shaving, 20 strops before shaving and 10 strops between shaving passes. Leather only.
If you carefully listen to the blade noise while stropping, you'll realize the change in sound that tells you that it's done, then a few more passes and it's finished.