How to Use Assassin's Mark? (Akali)

Hi, The best I've got is maybe, Akali could kite melee opponents by staying on the edge of the ring using 5-Point Strike and melee attacks. Would this strategy work?

My main questions are: How could we use Assassin's Mark, in general, to its fullest potential? How far is 500 units? How can we use Assassin's Mark on ranged opponents? Finally, how can Akali fight ranged opponents?

I thank you in advance.