I had this saved from another reddit post:

Step 1: Get a burner cell phone bought with cash by a homeless dude you pay with booze or w/e. Make sure you are not on camera and you wear glasses and a ballcap or similar, so the homeless guy can't ID you later. Step 2: Leave your actual cell phone at home the day you commit the murder. This way it continues to ping off towers nowhere near the crime. Step 3: Turn on your PC and setup a macro to browse the internet in your stead. Step 4: Get a gun that's unregistered to you, preferably with some type of suppressor. There are many ways to get one. Make sure you load the ammo into the gun with gloves on because the shell casings will have fingerprints on them otherwise. Step 5: Get a long sleeve black sweatshirt with black sweatpants and gloves. Also have on a hat and glasses. Most security cameras cannot identify you very well if you wear these things. You could even take it a step further and wear a fake beard. Step 6: Obtain a car that cannot easily be traced to you. If you have the money, buy a car for cash on craigslist using your burner phone to complete the transaction. Do the searching from public wifi, but that's just getting paranoid because you don't need an account to search craiglist, so you're not able to be traced just by browsing unless you send e-mails. Step 7: Dump any and all illegal stuff from your residence just in case, and prepare for the murder. It helps if no one is home and you don't have a security system, or you make it malfunction days in advance to not arouse suspicion. Step 8: Drive you unregistered car to the victim's residence and wait until he comes outside then shoot him in the body twice then in the head once. The body shots are easy to pull off even if the victim is running which will knock him down allowing you to get close then the head shot is to ensure he is dead. Now drive your vehicle to a rural area and torch it with the gun inside as well as the clothes and burner phone. Make sure you use gasoline mixed with Styrofoam and oil to cause the fire to burn longer and hotter. Step 9: Go home, turn off the macro and secure delete it using Guttman's algorithm(unrecoverable at that point) take a shower using some ammonia then go to bed. The ammonia ensures you got rid of any gunshot residue, so you can agree to a GSR test and pass further proving your "innocence." Step 10: If the police come to investigate, play dumb and consent to a search of the residence since you have nothing to hide. If they ask where you were say you were home surfing the web. The macro you setup will make it seem like you were home using the net during the murder. Your cell phone being at home also ensure it pings off the towers by your house giving your alibi two layers of proof. That's why it's easier to establish an alibi in this day and age. A person saying you're somewhere you're not is less effective because they could end up flipping on you. At this point, there's no way you could have gotten caught outside of bad luck. Like your car breaking down after the murder, or a cop happening to drive by at the precise second you shoot the guy.