Here's my opinion, take it or leave it.
On any rim. Put one side of tyre on first. Plan to finnish at valve on second side. Push all tyre bead(both sides) already on rim to center of rim, especially opposite where you are trying to get it on. Keep repushing tyre to center as you work it.
60%+ of experienced bike mechanics seem to not do this, but just use levers and force. I can get 99% of tyres on without levers using this method. Don't forget to add sealant before finishing putting tyre on. Tight means less chance of burping. Tighter the better IMO.
My Zelvy was hard, but not impossible by any means. Went up with track pump for this reason.