First of all, I really like the color pallette in this, it's very bright and summer-y and goes well with the theme of the picture. The background is nice, and simple enough to not distract from the character. Also the lineart is very nice, clean and crisp. The coloring is very good too. One thing (and this might just be me) but I would be expecting a bit more highlight in the hair, given the brightness of the sun shining on it.

One bit of critique on the anatomy, it seems like she has an exceptionally long torso, like I would be expecting the belly button to be a bit higher up, closer to where her arm falls across her body. Otherwise though, I think you did very well, I especially like the hair and the face, I think you did a great job on that.