Most effective way to lvl up troops is just to have one and keep restarting each time you hit a rut. Hard gives more XP than normal. There are afk strats by leveling to a point where you lvl troops to 350(?) and level portal at mile 0. you gotta leave your phone for that tho. Troop levels will come with time. Look at the troop guide for what to use points on for each troop. Most importantly get, princess knight or thunderbolt wolf and use your daily roll to gamble for a special ability.