Hello! Just wanted some input on painting my stormtrooper. I need ideas on to mark the squad leader of each squad. Any idea? Also, this is my first time painting, so I will post the pictures here when I am done.

I would recommend just making his right shoulder plate a different color.

There is no "squad leader" gameplay-wise. You can deploy an Elite Group or a regular group. As far as I know, Thematically, there are no visible rank insignia.

If you want to differentiate for gameplay reasons, you should differentiate in groups of three.

You can - as @RogueLieutenant suggested - paint one of their shoulder pads orange for them to be sand troopers (http://starwars.wikia.com/wiki/Sandtrooper , that is a bit awkward because there is the miniature of Kayn Somos with a correct sized Sandtrooper Shoulderpad)

- or take inspiration from the Battlefront computer game and paint one group as Shock Troopers (which is actually a card in military might) http://starwars.wikia.com/wiki/Imperial_shock_trooperand Shadow Troopers (Like Sandtroopers, that would be the wrong weapon, but who cares)

I prefer the Stormtroopers to be all the same to reflect that they are clones and strengthen the "army" look (it is an uniform, after all), so i marked their bases with 1-3 dots in different colors.

HaHa! Don't you think the Elite stormtroopers should be shadowtroopers and the Elite heavies be shocktroopers.