Is the 55 points inclusive of the state nomination/sponsorship points or not? Because the minimum points as of now is 65 points. If inclusive, then you need to meet the minimum points first.
Once you meet the minimum points, lodge the EOI and wait for ITA (invitation to apply). If you are lodging your EOI, it will automatically calculate your points based on the information you are providing and it will indicate whether you are eligible or not as far as I can remember.