My advice is to take a saint whose name you will actually use. That is why for those who have a saint's name already, I strongly advise they use the saint they already have. For those who do not have a Saint's name, but have something very similar or translatable, I will recommend they go with an equivalent. For instance, I baptized someone named Shari as "Agape." Shari can either come from Hebrew Sharon or it can be from French "Mon Cherie." The latter means my beloved. Agape means beloved; hence, Agape. I knew in this case that as an adult female living in an area with almost no adult Orthodox, it would be difficult to get her to use any other name, so instead of creating a strange duality where we call her one thing in Church and another at home, I used an adaptation.
My name before baptism was Dustin, which literally means "Thor's Son" and is totally pagan...there was a St Dustan, but the name is not equivalent. Others suggested I pick Justin, but that would be awkward too for people to call me Dustin/Justin and get it confused all the time. I ended up picking Anastasios for various reasons, and I do tell people my name is Anastasios, but at work (I'm a missionary priest, so I work a secular job) and such, people still call me Dustin...it creates awkwardness for me and I highly suggest that people not place themselves in such a position.