To access the PAINTED packs, you will need to have all 9 of the Sketchy Ink Skulls in your wallet and then you need to blend any 3 extra Sketchy Ink Skulls to get a PAINTED pack.
This feature is currently only available on NEFTYBLOCKS, but they don't do very good auto embeds, so you have to go to their website directly to access the PAINTED pack.
After you get a painted pack, go here to open it: https://waxdao.io/unbox/1185