1) ECM. The easiest/best way to do it, is to swap in a known good ECM. But unfortunately, most people don't have access to another ECM.
2) You can rent/borrow noid light testers from an auto parts store. That should tell you if the injector is getting a signal from the ECM to fire.
3) You can check all the fuses. Just pull them all and put a meter across them and make sure they all have continuity (or you can just look at them....although, occasionally a fuse will be burnt in two and you won't be able to see it). Another way to check the fuses is to use a test light and with the key on all fuses should have power on both sides of them.
4) Injector not firing. Fuel pump not running. No spark to spark plugs. Any/all of those symptoms can indicate a bad ECM.
5) The capacitors in the ECM should be replaced, whether or not they are bad now. Because if they aren't bad and causing the no start issue now, they more than likely will eventually. There are a couple of guys on zuwharrie.com that can rebuild the ECMs very cheaply, compared to other places and do good work. Their usernames are Surly and Redidbull. Look them up, if you can't replace the caps yourself.