Hi Burt Robin and welcome,
when I started amaroli some 1.5 years ago, I had to dilute 1 little spoon of urine in a big shot of water. Then I increased slowly.
In my experience the strength of the morning urine depends on the amount of urine present in the bladder upon waking up. If there is little urine, it is strong. In my case this is easily controllable with drinking a glass of water right before a go to bed.
But really, after a couple months of practice I stopped thinking about it. Strong, weak... I drink it all