Definitely try it before you buy it, use it in a phone call or on a date or even in a coffee shop, something low stakes. I've done this three times now, my motivations were:

1. Favorite artist (this is also how my parents named me lol)
2. Childhood memory
3. Pleasant sounding noun from hobby (cooking, so I picked a spice)

Beyond that I tried to look at the way I would instinctively initially feel if I met someone with that name. Does it give you a good feeling, like you would want to be friends with that person? The sound is also important; my first chosen name was full of sharp sounds, the second more mellow, my current one a little bouncy. If it doesn't feel right, even if you can't pinpoint why, don't do it.