About coin farmer and skill ticket

Hi there :)

Join the game a few months ago and being reading a lot of post but could not find out a definitive answer.

Thanks to several people I was able to save coins to get a Jedi Luke and more recently I pulled Gaston, Namine and buzz lightyear. So far only Jedi Luke is SL3.

So first it seems that I pulled good coin farmer however I am not able to chain skills at all which brings me to not amazing score (2 millions without boost)

I am wondering which tsum to invest skill ticket and more importantly how to get these ticket regularly?

Thank you so much!