Be sure to take your measurements before you buy your pattern.
Ready-to-wear sizing and pattern sizes are sometimes different.
Also, read the size descriptions at the back (I think) of the pattern catalog.
The suggestions to try something easy to start with are very good.
Another of my Mom's quotes: "Nothing succeeeds like success."
Which is why I like making quilts - almost any size can be used for something. :-)
If you have a consistent fitting problem with ready-to-wear, you will probably need to make some adjustment to your pattern for that same thing.
Also, patterns are drafted for a B-cup breast.