Professor Richard Wiseman found out about 10% of the 5,000 people he tracked last year were successful at achieving their resolutions by following these steps:
1) Break your goal into a series of smaller steps.
2) Tell your friends and family about your goals. This increases the fear of failure but also elicits support from them.
3) Regularly remind yourself of the benefits associated with achieving your goals.
4) Give yourself a small reward when you reach one of the smaller steps you mapped out.
5) Have a way to track your work - use a spreadsheet or a journal (blog).
Also check out these 5 tools at Make Use Of to help you with your resolutions.