Assign each tattoo a number. Then put it through a random number generator, preferably one that has an animation for choosing. As the animations plays it will become clear as you hope for a certain number, and thus, tattoo.

choose something with personal meaning

Is this person a professional and is this your first tattoo?

Because they hurt, real bad depending on where its done. I just started tattooing again after decades. It came back to me quick, but i still have to relearn some things, but know to keep it simple and relearn the basics again. Im hoping your friend is a professional and you get some kickass ink!!

Don't do it there. It sounds like a good idea right now, but 60 years from now when that particular area sags (I assume you mean upper arm, which will 100% sag), you'll regret it. Put it in a spot that won't sag with age... and make sure it's something you'll be fine looking at 60 years from now (that part I can't help with, only you know what speaks to your soul.

and @flyingoctopus that's actually fucking brilliant.

Not upper arm, more like a bit below my wrist. And the three tattoo ideas I mentioned are all from things that have meant a lot to me growing up. Almost considered a Steven Universe tattoo tbh, but I feel like I'd be constantly ashamed of it, or be judged all the time. So far I'm probably gonna go for the SPQR tattoo, because of how much I enjoyed the Heroes of Olympus series.

Have your friend do it in permanent marker first and see how you like it. That way you can try all three out.

Honestly? Don't get a tattoo from a friend. If it doesn't come out perfect you could end up resenting them and ruining your friendship.
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If you're absolutely insistent on doing this, then ask yourself: Has your friend done tattoos before? What did they look like? Can they manage the fine detail in the design you want? Does your friend have the right equipment (i.e. sterilised machine and needles, high quality inks, sterile room to do it)? Are they offering to tattoo you for free or for a price? If it's free, is it because they want to practice their skills? Do you really want to permanently live with their practice on your body?
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A bad tattoo can wreck your life, either from an infection or because you have to look at its horribleness every day. I say this as someone with plenty of tattoos, both meaningful and not (one is literally a potato, lol) but I don't regret any of them because I had them done the right way.

They have done tattoos on their brother and themselves. I've seen it, and it's really good. Wouldn't have considered it otherwise. He also paints.

@captainjackharknes forsure, that's a good spot.
@unicycle all hail the glorious potato.

@funkmaterrexx I'm 51 and was a professional tattoo artist decades ago. I'm 51 now and just got myself a personal set up for a hobby to tattoo myself and my husband. I'm definitely sagging but it doesn't matter if the heart is there. I love the work I've done on my left wrinkly hand, ankles and about to donon my calf, knee and thigh. We all age, and differently at that. As long as the person is aware of this, and how could one not be, go for it! They make me so happy. Like my dreadlocks. Our style is a personal choice, meant for us, not others. @captainjackharkness, yes, be aware of the field/ work you are aiming for because there might be prejudices against it. But that something for you to weigh. And location you want it at is great for a first tattoo. In the past, I e always recommended the shoulder, upper forearm or calf, all easily hidden if necessary and the pain is not that bad, compared to say, your ass cuz that hurts!!! Sorry if I got the names or how to do it wrong. Peace!!

Now I'm gonna have my morning potato lol

So someone brought it to my attention that the tattoo I wanted from the Heroes of Olympus series, which is the Roman SPQR, is actually a very common tattoo in the Navy...

Where did it originate, that's whatvid ask myself. The original suaztica, is a religious icon in the cultures of Eurasia. The left-facing version may also be referred to as sauwastika. It is used as a symbol of divinity and spirituality in Indian religions. So, there's that. If you dont want to offend anyone, can you have your artist make it more personalized for you?

Eh I just decided not to go for the spqr one, I live in an area where a lot of people could take it as I'm pretending to be in the army.

A lot of people dont do that, research what they get. Good on ya. You do what you feel is right.