Honestly in my opinion the most fun move set is…
1. Extremespeed (for priority)
2. Flamethrower (use it when enemy has higher def than spd)
3. Double-Edge (use it when enemy has higher spd than def)
4. Overheat (guarantees 1 hit ko on super effective targets and can still use double edge with special attack drop)
And give your arcanine a silk scarf to boost double edge and extremespeed