Be careful when you do this! Many applications include a section (usually right near your signature) stating that by signing this you declare that everything you've written in it is true and complete to the best of your knowledge and that you have not willingly falsified or left out any information under penalty of perjury (and various other wording to the same effect).
If your application has this and you fill out the section for professional references with personal references then you have technically committed a crime. Now, 9 times out of 10 nothing will ever come of it, but down the line they can use it as an excuse to not only fire you, but to press criminal charges and possibly claim damages (I.E. it gives them ammunition for suing you for money, whether or not you lying on your application actually lost them any money. They can make all sorts of claims once they have proof of dishonesty)
If you're going to do this kind of thing, here's how to make it real (and thus, no longer perjury):
You and your friend group should work on projects together and take turns, per project, on who is the "boss" supervising the project. These can be anything from organizing a canned food drive for the local Food Bank, to picking up trash on the sides of the road or on a beach, to beautifying a public garden, to trail-clearing, etc. Make sure all the projects are volunteer work type projects because 1) volunteer supervisors count fully as professional references! and 2) volunteer work always looks good on a resume.
You don't technically need to volunteer through a non-profit organization, but the name-dropping often helps for legitimacy. So, if you're doing the food drives, for example, you can say "I worked under [your friend's name] organizing quarterly neighborhood food drives for [Name of Food Bank]."
If you guys go hiking and you pick up trash along the trails, touch base with the local park rangers to say "hey, our group does this thing where we help beautify parks by picking up any trash we find on the trails. Can you tell us where the bins all are?"
Then, if/when the employer follows up, the Food Bank or Park Rangers know you enough to say "oh yeah, that group comes by all the time. The to good work!" Ta-da! You've now given your non-existent volunteer group legitimacy, and so when you say you worked under your friend doing this project you are now telling the complete truth.
Your volunteer project can legit be as simple as offering to put up fliers for a fund raiser. "I worked under [friend's name] for the [fundraiser event]." "Oh? What did you do?" "Mostly helped out with the marketing doing the advertising."
You can spin a LOT if stuff into legitimacy for your applications and interviews without needing to outright lie and risk being caught out committing a crime.
Do what you need to get the job, but Be Smart about it. Be safe and cover your ass.
