Ahhh, this provides a little more color than your original post. Hmm. I would really continue trying to find a better FT position. I know so many international students that struggle to find sponsorship and end up with more education and no better employment position.
If you really want to do an MSF I would focus on taking the GMAT right now. Once you do that get your resume in order. Check out the template on Mergers & Inquisitions. Also, try your hand at networking. It is one of the most powerful tools out there for finding a better job and it is something you will need whether you do an MSF or not.
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