First your gonna need to know the gas to oil ratio on your 2-cycle engine whether its 32:1 or 50:1. On a standard weed-eater the gas to oil ratio is 50:1. but on a high performance dirt bike it may be 30:1 it all depends on each machine you use. It doesn't matter what type of oil you use as long as its the right ratio and isn't conventional oil, you want full synthetic for all 2-strokes.
Step 1: GRADE OF GAS
On EVERY 2-stroke or small engine of that matter you ALWAYS want to use the highest octane of fuel you can get. It helps your engines performance and longevity.
Step 2: OIL
Get yourself a full synthetic 2-stroke/2-cycle oil it will make your engine last a whole lot longer. Compared to conventional. Never run a 2-cycle engine WITHOUT OIL!
Step 3: How to Mix the Oil and Gas
Get yourself a 1 gallon container rated for gasoline at a lawnmower shop. Then pour the oil into the container, and go to a gas station and pick the highest grade and fill her up. After you have completed that you SHOULD shake the gas and oil container. Do that every time you fill the engine up with gas.