Hi i'am almost a begginer (with my Bezzera) but i'll try to give you some info:
First you Mazzer Jolly is great, you can alway go for more but you have a very good grinder, forget that
Try around 16 or 17 Gr in pf for around 30-36 Gr in cup.
Find the grind setting that make the first drop start to fall on you pf (naked portafilter is perfect) just when the pump finish to fill the group, then just press up the lever to release it and let it do his job, remove the cup when blonding
When you'll have good result (you can have Very good just with that) you can try have fun make start the lever before the pump finish to fill the group, retain it...
Of course look the videos on the first page here Bezzera Strega - Second Look
is very ionformative
Use warm cup