[Presto]

Congratulations, OP!

If at all possible, take your soon-to-be fiancee ring shopping. I know you want it to be a surprise, but buying the ring together will ensure she'll get a ring she loves. Chances are, you may get one that she'll appreciate, but she will be constantly comparing her ring with others that come into her field of vision.

After we bought the ring, there was still the surprise of when/how I would propose, so there's still some mystery and anticipation there. To this day, my wife still adores her engagement ring. If I had picked it by myself, I definitely would have fucked it up!