When you go shopping for grill cleaning supplies you will find all kinds of different cleaners and tools, but from our experience, and for this tutorial, this is what you will need:
1. a long-handled wire barbeque brush
2. a wire bottle brush
3. plastic putty knife
3. wet-dry vacuum
4. washtub large enough to hold grates
5. grease-cutting dish soap like Dawn
6. cleaning vinegar
7. baking soda
8. long rubber gloves
9. scrubbing sponges
10. large kitchen sponge
11 larger microfiber towels
12 stainless steel cleaner

To clean your gas grill, start up the grill, close the hood, and let it come to full temperature. Wait at least 30 minutes for the extreme temperature to burn off any stuck-on food or grease.

Open the lid and dip your wire brush into a bucket of warm, soapy water and scrub off all the carbon from the grates.

Then turn off the gas, and disconnect and remove the propane tank. Let the grill cool completely.

For a charcoal grill, first, dump the old charcoal briquettes into a metal container. Then, scrape away any caked-on charcoal dust and debris with your wire barbeque brush.

Once the grill is cool, remove all the grates and flavor bars and totally submerge them into a tub of warm, soapy water, and let them soak for at least 30 minutes.

Remove anything else from the grill that you can easily take off, such as burner-control knobs, warming racks, and grease trays.

The burner tubes on most gas grills are removable, too. Just look for the single screw or cotter pin on one end of each tube.

With the grill grates and flavor bars removed, the inside of the barbeque, called the firebox, is exposed and ready to be cleaned.

Start by putting an empty bucket underneath the firebox, directly below the grease tray opening, to catch anything that might come out.

Use a plastic putty knife to scrape off any caked-on gunk from inside the firebox.

Use a wet/dry vacuum to collect any remaining loose debris.

Then scrub the firebox with soapy water and a scrubbing sponge.

Once the firebox is clean, rinse it out with a garden hose.

After the grates and panels have soaked, take them out and scrub them with the wire brush.

For really stubborn gunk, mix a paste of white vinegar and baking soda and apply it directly to the worst caked-on food bits then scrub with the scrubbing sponge.

Rinse all surfaces clean, making sure to thoroughly dry cast-iron grates to avoid rusting.

This is the time to inspect any porcelain grates or porcelain barbecue housing for chips, which may eventually lead to rust.

Repair any chips with porcelain touch-up paint.

Inspect your burners for signs of corrosion or for anything blocking the row of flame-emitting holes.

Burner tubes are inviting spots for spiders to lay eggs if your grill goes unused for a while. Take a wire brush and brush back and forth across the row of holes.

Then use your wire bottle brush to clean out the inside of each tube.

Empty the bucket of dirty water, then refill it with clean water and a few squirts of dish soap. Now scrub down the entire outside of the grill using a large kitchen sponge. 

Be aware that steel wool, metal sponges, and coarse scouring pads can cause scratches, so avoid using them on finished surfaces.

After washing the outside of the grill, use super-absorbent microfiber towels to wipe down and dry all surfaces.

Stainless steel cleaner works great as a final touch, but it’s not designed to remove heavy buildup or baked-on gunk.

When cleaning stainless steel, wait for an overcast day; the hot sun can make it hard to remove streaks from stainless steel surfaces. 

Spray on the cleaner, wait a few minutes, then wipe it off with a clean, dry cloth.

If you don’t have stainless steel cleaner, try using undiluted white vinegar. Unlike stainless steel polish, vinegar is also effective for cleaning stainless steel surfaces.

Once the grill is sparkling clean and thoroughly dry, reassemble all the parts you removed, taking care to fix the burner tubes back into place in proper position with cotter pins or screws.

Finally, rub any cast-iron grill grates with a light coating of vegetable oil.

Finally, reconnect the propane tank, close the hood, and fire up the grill. Let it heat for at least 15 minutes, then turn it off.

This initial firing will help burn off any cleaning residue, season the cast-iron grates, and serve as confirmation that you reassembled everything properly.