You'll get alot of members with some different techniques but essentially the same.
I start by cleaning the stock paste of the cpu using a soft lint free cloth and 99% isopropyl alcohol.
When i'm ready for cooler mounting i apply a 5mm pea sized amount of compound in the middle of HS.
Some compound is not very co-operative so i have also used another method which involves applying the compound in tiny dabs in a grid covering the HS.
Both have worked well for me.
Your first time will involve a little patience.
Btw i've tried the plastic card spreading approach and was never successful but i think it was a matter of the compound i was using .
Thermalright ChillFactor 2 which is very good btw but not for spreading.
In the same class as AC MX-2 and AS5.