You need to talk to your designer/developer. Every developer has a unique skillset; some will handle the whole build process. Others are able to deal with one or two stages only.
Typically, the sequence of events looks something like this:
It's possible that one developer will handle this whole process. In situations where there's a team working on the site, you need to ask each team member what their requirements are, and what they expect to receive from you in order to complete their part of the job.