User blog:Myga/Help making different types of squads!?

I basically want some ideas for Trail, Vortex, Frontier Hunter, Frontier Gate, Spark, Crit, etc... Squads. I'm a f2p & I don't have luck what so ever so I have a lot of bad units... :c

My units ( 3* - 7* ):

http://imgur.com/a/HmA9p