During your first visit determine which job category best aligns with your objective. You may find more than one but be picky, limiting the number to no more than two or three. The overarching goal here is efficiency - the ability to quickly pop in and check the lists that best suite your needs before popping back out, without wandering all over the site.
A more specific goal is to find the low hanging fruit. These are job postings that match perfectly with your objective. Here's where it pays to be picky and discriminating. Look first for the ads that are obviously right up your alley. If there aren't any, you have a choice - move on or look for close-but-not-quite postings.
If you decide to move on, which is to say STOP right there, you'll probably be making the right choice. If you do hang around, do it consciously employing a dash of Genghis Khan - be brutal and brief - otherwise you can spend considerable time mired down applying for jobs that others are better positioned to get. Yes, there's always a chance but if the odds don't favor success don't invest the time.
Once a job ad is selected, follow the contact and application directions exactly. Repeat, exactly. Typically you will be asked to do one of three things - apply at a separate website, fax your documents, or respond to the ad by email.
When responding by email, I recommend the following.
Begin by giving your response a title that matches the ad so it is easy to spot in a full inbox. Next type a short cover-letter like paragraph, three or four lines in length. Keep it short and sweet, mentioning any requirements or qualifications listed in the ad and how you stack up. Conclude by mentioning that you are looking forward to introducing yourself in person and then sign off with a sincere thank you. From there, drop down a couple lines and paste your resume right in the body of the email (unless the ad instructs you to attach it separately). This way your brief cover-letter-esque reply and the top portion of your resume can be seen easily in review mode, the way most of us scan through unread emails.
As a general rule, the strongest job leads are created by job seekers themselves. This is not to say there isn't a place for job sites and postings - but - they can be black hole time suckers, consequently their use needs to be managed or they will manage you.
John Jeffrey Lundell