A "GRID" is nothing more than what you will write on your PCS packet during your cpne. Its a form *you* use for yourself to jog your memory. Kind of like what you use during work to remember to do things!
Everyone's grid will look completely different, because it's unique to YOU.
Do you have mnemonics yet? Or are you not going to use them? The most common grids have mnemonics in them, that help you to remember the Critical Elements. That's all a grid is.
So say you go into your first PCS, and you're assigned Abdominal Assessment, Neuro Assessment, and Specimen & Drainage Collection. On the blank piece of paper in your packet, you will write down your mnemonics for the Required Areas of Care: 20 min checks, Vital Signs, Mobility, Fluid Management. Then write down your mnemonics for Abdominal Assessment, Neuro Assessment, and Specimen/Drainage Collection.
You may want a mnemonic for actions you must do every time you leave a pt room (bed low, call light within reach, etc). You may want to write down any equipment you'll need to do your Specimen/Drainage Collection (your Ce will write down WHAT you are to collect obviously, this is just an example).
So that's what a grid is. Do you plan to take a workshop? Do you belong to any online yahoo groups? There's a ton for the CPNE. Do a search on Yahoo. They all have mnemonics online too.
The best thing for YOU to do is to figure out HOW you want to remember the Critical Elements. Those are the be-all, end-all of this exam. If you choose to remember them with mnemonics, then figure out mnemonics, or find someone else's mnemonics online and use those. Whatever helps YOU. Then you need to work on memorizing and understanding those Critical Elements.
Hope this helps.