I really recommend buying an ehrlich and marquis test kit. You can get both with strips and test charts for about 25 dollars on amazon. Biological drugs such as weed and mushrooms are easy to tell potency by looking at or smelling, but with your synthesized compounds the senses fail. I super recommend LSD, my best advice with dealing with though is that you can always add too, but it is very difficult to take away.
RE: My experience doing a "heroic" dose of psilocybin mushrooms.