You should have frequent meetings with your bosses and ask them about what else they expect from a person in your position. Note down all the details and try to do some extra work as efficiently as possible.
Try to be as proactive as possible. If you really want a promotion, never ask your employer ‘what’s in it for me?’ instead, you should be willing to volunteer yourself for the extra work and make yourself prominent in the organisation.
To improve your skills, you should search the internet or visit institutes for the suitable courses. You should take the course, which complement your area of expertise or that enhances your field knowledge. After you know the courses, you should choose a viable institute; prefer studying the course from a reputed and well recognised college otherwise it will be of little worth.
To increase your knowledge, you can also take in the professional development courses or certifications that are offered by the industry association.