HI,
I have written a post on gmatclub regarding how to do gmat preparations(link in my signature)
Yes its very much possible to achieve a score of 45+! You just need to keep practicing!
Follow a theory -practice- theory cycle.
1. Take a topic
2. Read the theory
3. Go to grockit and do easy questions or go to gmatclub tags (link in my signature) and do 500/600 level questions on that topic
4. If you do good then move to medium difficulty else continue with easy problems.
5. IF you do good then move to hard problems or go back to theory.
6. Once you are done then move to the next topic.
Prepare a progress chart (day-by-day) (topic-by-topic) progress. Something like this
Prepare a xls sheet (topic by topic).. and keep a track of your progress on a daily basis. Use color coding (Red,Orange,Green).
Red: You are weak in theory - brush up your concepts.
Orange - Done with theory but weak in application of the concepts
Green - Done with the topic
Once you are done with the theory then start taking mock tests and prepare an
error log (you can search in gmatclub for error logs)
Good Luck for your preparations!
Hope it helps!