Start with the basics... you need fuel and spark for it to run. Check and see which you are missing. You can press the schrader valve in to see if you have gas pressure present at the fuel rail, or just add a little into the throttle body and try to start it. If it fires and runs the gas out you know it isn't getting gas. If so, try checking the filter, inertia switch, fuel pump relay, or fuel pump. To test the spark, you can take a plug out, put it back inside its wire, ground the outside of the plug to metal, and have someone crank it around to see if it sparks. If no spark test the coil, etc, but at least you'll know where to go from there, either gas or spark. If you happen to have both gas and spark, try checking the valve timing- leave the plug out, put ur finger in the hole it came out of, have someone crank it over and see if the plug fires a split second before you feel compression, or about the same time. If this is off, you may have jumped a timing belt or chain. The last test is primitive, but it should get you started down the right path of figuring out whats wrong with it...