I'm a crocheter turned knitter who knits continentally and just recently got comfortable with purling the correct way.
How I finally got it was by figuring out a way to hold the working yarn: I wrap it once around my pinkie and twice around the top section of my pointer finger.

This keeps it tight and easy to grab. I have to hold my purling yarn tighter than my knitting yarn, which may be the case with you, too, to help tight up your stitches a bit.
I had been purling the wrong way (by grabbing the working yarn so it was behind my needle), but that only meant that I had to knit through the back loop. I will probably continue to do it that way when I just do straight stockinette on something because it is soooo much easier to purl that way.
However, I started the Clapotis (which is the project in the picture), which meant I had to learn how to purl the right way because the Clapotis pattern makes you knit through both the front loop and the back loop, so the way I was used to knitting would have been too confusing for me.
Good luck and I hope this helps a bit.