you can do that but you have to be careful not to get too close to the mold or else it can stick really bad and ruin your mold. I personally didn’t heat the mold with a heat gun, I heated the resin inside my cup before anything to prevent mistakes
you can also make your own alcohol inks very cheaply with markers and strong alcohol there's a lot of different tutorials online. just make sure not to use too much alcohol if you do let it dissolve so that the color can be super concentrated so you don't have to use a lot because if you do your resin will not fully cure
For the pink one, the measurement is 50mL of resin and 50 mL of hardener. For the blue tray, I used 55mL of resin and 55mL of hardener. Hope this helps :)
