How can I best position myself for getting a clerkship with a firm in the fall?

A lot of the same rules apply in positioning yourself for jobs in the fall as for summer jobs so rather than repeating my whole answer, I'll dwell a little more on the networking aspect.

From my experience, I can tell you that hiring is almost as painful as looking for a job. Looking through stacks of resumes and trying to identify who seems best on paper is only the first step. In a typical interview, you have 15-30 minutes to get to know someone, decided if she seems competent, get a feel for whether she'll fit in with everyone else at the firm, etc.

Half the time you are going by your gut, and what you get and how they'll do is very chancy. The process from advertising a position to hiring someone to the new person's first day on the job can take weeks and weeks. If I am looking for a person to fill a slot that is going to be vacant in 10 days because someone just gave me notice, it will be much simpler for me to go to someone I already know and who I know is looking for a job.

Involvement in activities where you can meet alumni - like Phi Alpha Delta alumni events or other bar events - is a must! When you meet these people, follow up with a simple e-mail, ask them for advice about questions like this. Let them think you’re someone who's a go-getter. If something comes up at their firm or at a firm they do business with, yours might be the name that pops immediately to mind. Even if the attorney with whom you are networking seems low-level at her firm, her hiring partner might listen to a recommendation.