Before you even think about actually making a bid on subcontracting work, there are some things that you need to do to improve your chances for success. Finding the "right" prime (i.e., one whose products or services match your capabilities) and effectively presenting yourself and your company are going to take a little forethought and more than a little preparation.
To adequately prepare, you need to take action in each of the following areas for each prime that interests you: