Police knows how to deal with force, the goal of the protest should be to not give it any opportunity to apply the force, so that even the people who are against protesters can't find a way to justify police actions.
It may be too late for applying this tactic now, but if it was applied earlier it would make the protest much more successful. At least that's what happened in Armenia few years ago, when after many years of unsuccessful violent protests, non-violent protest brought a real change.