You probably already know that you earn points much faster on slots than on VP.
I forget the formula, but it the difference is significant.
Also, TIME PLAYING on one machine adds points faster than jumping from machine to machine.
Find a machine you like and stay on it as long as you can.
Watch the meter.
Try to play it until you have 250 or 500 or 1000 tier points before you give up on that machine.
Even the so-called penny slot machines, if you play full coin you can earn tier points faster than you think.
But watch the meter and stay on the machine if you can, up to 250, 500, 1000, etc.
BTW, it can take CET a few days to actually update your points on their web page.
So don't panic if when you first log in at home or wherever, you don't see your new tier points.
They'll catch up in a day or three.
Good luck!