I did a search for diagnosis of some of my symptoms and came up with high cholesterol. what do doctors look for to diagnose it?

Blood test: Lab test on blood specimen drawn after an overnight fast is sufficient to diagnose high cholesterol.

Serum test: Cholesterol is divided into several different types, with the major groups of LDL (low density lipoprotein) and HDL (high density lipoprotein). Hdl is "better" than ldl, but it is the ratio between the two along with the absolute value (should be <180) that is important. Cholesterol and triglycerides can alter your risk for heart disease, vascular disease, and stroke.

Lipid panel: Ask for a fasting lipid panel (blood test), with a "direct ldl." that way you'll get good results even if you triglycerides are very high.

Usually asymptoamtic: A fasting cholesterol blood test is the most accurate way to understand whether or not you have abnormal cholesterol levels. Best of luck!