Here are my three personal favorite ways to clean my engine:
1) Simple Green. Get a bottle of simple green and a tooth brush/brush and clean the engine bay. Just follow the instructions on the bottle, and steer clear of your distributor. Easy, and works good. Not too bling bling but clean.
2) CD-2 engine detailer. Two cans, one cleaner one blinger. I use this when I really want to impress the ladies. Really straight-forward. Follow instructions on cans and put on some sun glasses. This shit honestly works awesome. Two step process - works amazing.
3) Engine brite. A can of this shit is like $.99 so if your a cheap bastard like me use this method. Again follow instructions on can and thats it. Works good not as bling as the CD-2 method though.
Good luck.