1. You need a Good GRE score, preferrably above 1450.
2. A good TOEFL score - this shouldnt be too difficult
3. Work experience is fine, you can connect that with your studies in your Statement of Purpose. I have friends who worked for 3 years and then did their MS. Obviously your resume would be a bit stronger, especially if you show, how your past education, work experience and the course you are aiming CONNECT. Basically you need to show you have a plan.
4. If you have white papers or research publications that will strengthen your profile. If you dont have this, but only work experience, then you can obviously use your work experience to cover up that weakness. You could talk about any patents you filed at work, or you could talk about any projects you did, and how it relates to your ambition etc.,
5. Aid is based on Gmat score, GPA etc., So try getting a good score.
6. Statement of Purpose - Very important. Make sure you are very specific, about what you want to do. have a short term goal (right after the degree), long term goal (5-10 yrs). Create a storyline, about how you did whatever you did (getting into engineering college or whatever, the challenges, the decision making effort, your projects in college etc), and how you got into your present job and why you wanna get a degree in whatever course you wanna do, and how a degree from this particular school will help you in your short term and long term goals. Also talk about how YOUR profile, experiences etc make you unique and about how your experiences will serve the community at the school.
That last part will take a lot of time and effort
But go for it!