The process is simple. Purchase a grinding machine of some sort, from a food processor or a home grinder or attachment (like to a KitchenAid Mixer) or a dedicated manual hand or electric grinder. Prices vary widely, from $19.99 to hundreds or even thousands of dollars. Remember, you get what you pay for. Used equipment can also vary widely. But in all cases, especially electric ones, a guard to protect your fingers is mandatory and do not modify it to remove the guard; it is there for a reason. On manual models you simply stop turning and protect your fingers with little or no damage. But an electric one can chew off your fingers before you can stop it. Have great respect for all machines!
When cooking beef (whole muscle beef) such as a roast or steak, you cook from the outside-in in most all cases, to a recommended temperature for the piece. But, with ground beef, which part is internal and which part is external? You don't know, because it is now 'ground up'; the outside is inside and the inside is outside. Any bacteria that has formed on the outside of the piece is now ground into the inside, and the inside is now ground into the outside, giving more surface area to be contaminated by the grinding. Wow! Pretty complicated!
But, with extreme care, you can make your own ground beef successfully. The entire operation must be performed "CLEAN". Or at least as clean as you can make it.
The first step is to sanitize. Rather than misquote anything, I refer you to an article on making bleach sanitizers; http://ucfoodsafety.ucdavis.edu/files/26437.pdf
As the article states, one tablespoon of chlorine to a gallon of water would yield 200 ppm (parts-per-million), maximum concentration. So, thoroughly washing all parts and surfaces, then rinsing in clean, potable water, then sanitizing in sanitizing solution and allowed to air-dry for 5 minutes minimum is the recommended procedure.
Wash hands with sanitizer whenever they become soiled.
Next, once surfaces and all equipment and all articles are prepped, bring the beef out of the refrigeration and inspect. Look for decomposing parts, such as black or brown edges, and trim away and throw out. Re-sanitize the surfaces (wipe with sanitizing cloth). Remove any bones or tendons or ligaments. Re-chill often.
Once meat is prepped, put together all parts of grinder. Use approved food-base oil (such as Haynes[emoji]174[/emoji] Spray) for lubrication. Do not use vegetable oil, it can turn rancid.
Haynes[emoji]174[/emoji] Spray: http://www.butcher-packer.com/index.php?main_page=product_info&cPath=3&products_id=40 one possible source
Grind your beef according to unit's instructions. Most preferred method is to grind twice through small-hole plate, cleaning any debris from cutting blade between grinds. If you prefer, you may 'chill' your beef before grinding into a semi-frozen state, but do not over-work your grinder's motor unnecessarily.
Immediately, store in clean, sanitized airtight container in the refrigerator. Shelf life is 1 day. Use it or freeze it.
Then, tear down and thoroughly wash, rinse, sanitize and put back together, with sanitary lubricant, all articles and equipment.
That is the process!