I don't use Epsom Salts either. They are way too harsh for my body. I tried them once on their own (ie not on a Liver Flush day) and it was such a horrible experience I knew it wasn't for me.
I've done 5 flushes so far. I use Mg Citrate (Nature Calm). On the day of the flush, I just drink the fresh juice of beets, apples, carrots and Celery and then Mg Citrate in the evening, repeating the Mg citrate drink twice the next morning. I actually mix in a tiny bit of prune juice into the Mg Citrate drinks as well (only in the evening doses though), as prune juice works great for me as a laxative. I also drink a few cups of chamomile tea with fresh lemon juice mixed in on the day of the flush.