It might be easiest just to buy a few bottles of juice from somewhere to refill the cartomizers you received with your Bloog.
VaporBomb.com is having a 20% off sale this weekend, the code is on their home page. You can look at the different flavors of juice and find some that match the flavors you received in your pre-filled cartomizers.
It would probably be easiest at first not to vape your cartomizers dry, but to add 5 or so drops in the top at a time to keep them damp. I believe you may have auto batteries and you do not want to take a chance of having juice/liquid get into the battery.
70/30 is a good mix. It's enough to give throat hit and produce vapor. The higher the PG ratio, the more throat hit; the higher the VG ratio, the more vapor.