Few mistakes,would point them out for better methods next time.
-You SMSed her to ask her out.This actually depicts to the girl that you're not willing to talk to her in person or with a voice,whatever the reason.
-After she declined to go out with you,you still made a nice comment about her,which in no way makes you look confident.It actually tells the girl that you're going to be with her no matter how she treats you.
I truely believe that SMS is a very useless form of communication.It gives a person long time to think about what they want to say,which would totally be different from what they would've said impromptu.
Ok,so here's what you can do with this girl.
1.You can try one more time to ask her out,after 4-5 days.Call her this time or do it in person.If she declines,just say,'Too bad....For you'.And next her.
2.Don't make it a big deal that she declined to go out with you,just act as if nothing happened.It would make you look suave lol.And don't give her too much attention.
3.Talk to other girls in front of her,make yourself look like a really big PRIZE.If you do this correctly,you're gonna be charming.Read articles on charisma to know more.If you do this,there's a high chance the girl would go out with you next time you ask.
These are 3 things you can do.If I were you,I'd do the first one so that I don't waste time on just one girl and turn it into a one-itis.However,the 3rd one is pretty good too,it gets you acquainted to a whole lotta new girls which is good.
Cheers!