Basically that depends on whether you are looking to learn to customize it or use it for your work. For the initial case, I agree with the previous answers - the first thing you need to check is the SugarCRM forums, there you also can ask specific questions (although there's no guarantee someone will answer, however it's worth trying I think). For the second case: 1) Watch video tutorials 2) Read tutorials 3) Work with it until you feel confident. The above points are only of use if you combine them with practice.  

Posted By: Vibhor