I have decided that I need to do an MBA (it's one of my new year's resolutions). I've been reading through a lot of the posts and I guess I might be too late to apply for fall 2016, since I haven't even taken the GMAT. I am wondering what I can do to get myself ready for the next intake. Here is my profile:

BA in econ.
Undergraduate GPA (converted): 3.3.
Work experience: 1.5 year sales analyst for an IT company and 1 year marketing manager for an internet startup.

I have another 1.5 years of work time until fall 2017. I enjoy my work for the internet startup but I can also consider getting another job for the next year or so if it helps my MBA applications.

Other than that I am confident that I can get a 700+ on the GMAT.

I am mainly interested in top US schools including Booth, MIT, and Columbia. Is my profile good enough? I realize that my work experience will be low for these schools, so is there anything I can do to make up for that?

There's no answer to your question that fits the length of a forum post: there are many books on the topic. Start with http://find-mba.com/articles/standing-apart-from-a-highly-competitive-mba-applicant-group and http://find-mba.com/mba-faq/am-i-a-good-mba-candidate

Yes, you are right to be concerned about your lower-than-average work experience. As for staying with your current job or getting a new one, that can be tricky. If you were going to get another job, you'd have to find something that you can somehow connect to your other positions as well as to your post-career goals.

For somebody in your position one good piece of advice is to get a great score on the GMAT and to make sure that the score is balanced. Also, consider other parts of your application: have you demonstrated leadership ability outside of your job in the form of volunteer work or another area? If not, you basically have a year now to get some.

Appreciated. I've had some stints of volunteer experience, mostly unrelated to my career goals, and I've also done some pro bono marketing and strategy consulting for a few startups. I certainly plan on continuing these endeavors. The GMAT I am not too concerned about but I will also use the next 6-8 months to study.

Thanks!