The first thing I need to say is that my theories on job application, resume and cover letter writing, etc. are my views. For every manager who kind of likes what I suggest, there are at least 12 that prefer everything from variants to the opposite of what I suggest. Your mileage may vary.
The second thing I need to say is actually what those things are I plan on saying. Er. These are the things I do and look for when people are applying for jobs to work for me or my company:
Spell check my resume. You'd be surprised how few people do this. I would also have a human do it, because Word may be down with you saying "hear" when you meant "here," but people who are wondering if you are as detail oriented as you claim will get a negative impression when they notice the homonym instead of the correct word. Spelling your own name in more than one way on a resume counts as a misspell in my book unless you specifically are making a point of telling me it can be spelled more than one way...though I'm not sure why you would do that on a resume. "See, I go by Holly or Hollie..." You go, girl, you.
Have someone, who is not me, read my resume. Preferably I want someone who is not especially technical to do it. Does it make sense? Do they understand what I've done in relatively plain words so all they have to do is look up the acronym/code phrases/etc.? Typically, your resume has to be screened before someone that you'll be working with looks at it daily, and those screeners REALLY appreciate a clear and easy to read resume; it makes the difference in whether yours gets tossed into the "eh" pile or the "prospect" pile. Yes, people who are not as technical as you are may be vetting your resume. Accept, move on.
Keep my resume to 2-3 pages. Back in the old days, one page was fine; but people no longer stay at companies for five or more years...and in the age of consulting and contracting, you may have a lot of gigs. Regardless, keep it as short as possible; 3 pages max. While many schools of resume writing indicate you should explain every "t" you've ever crossed and wax philosophical about all the "i's" you've dotted, it is PAINFUL to read a really long resume full of repeated buzzwords. I have also been known to copy buzzwords from the resume and quiz participants on those buzzwords, so you might want to stick to words of which you completely understand the meaning.
A side note: privately, if you use any of the major buzzword bingo words in your resume--eg: Paradigm--I'm less likely to want to even interview you. I'm probably alone in that, but the lesson to take away is to use unique words that explain stuff, not fancy words that I might cross examine you over or make you spell in an interview. Oh yes. It wasn't my finest moment, but I did it.
Try not to repeat buzzwords. Oh, for every industry/job there are buzzwords that make people reading your resume feel comfortable you have some clue of the job you're applying for. But keep them to a minimum. See the bullet up above about someone who is not you reading your resume.
Do not include an objective. This is a purely subjective judgment, but basically you are either saying "My goal is to be patently vague so I can reuse this resume multiple times" or "My goal is so utterly specific to the job description that its as if I might be lying to you that my whole life is wrapped around the one chance to be part of your company." I honestly don't see any value in either, especially when you need to capture additional work experience (since as you move forward, your resume is only going to get longer). On a sparse resume--where you have one or two years experience only, or you are trying to change fields, then an objective is more tolerable. But my general preference is skip it.
Target my resume. When I'm submitting a resume, I want to make it as easy as possible for the person reading it to realize why, just from looking at my resume, I'm the person for that job. If I'm going for a Quality Assurance Manager position, I'll reduce the amount of time I spend explaining what I have done in various positions as a Project Manager, and spend more time explaining everything and anything Quality Assurance I've done. People do not like to dig to find out information they really want to know (and possibly have a stack of other people giving it to them more easily than you are).
Don't lie on my resume. People will ask me about things I've done, and they'll want specific answers. You might pass a screener, but if you cannot do/don't have the experience/knowledge of something, you're pretty much wasting your time and the time of the person asking you the more in-depth questions. This is BAD. Even if you don't get the job, you want them to feel positively about you, or at worst, not negative about you. Most industries of the world do in fact talk to each other, and you may have trouble finding work if you're called on what you've put on your resume.
Submit, even if you don't have the exact qualifications. I don't, for example, apply for CEO positions at Fortune 500 companies. However, if I have all but two of the technical requirements for a specific position I can do, I'll send in my targeted resume, anyway; some managers like to use that initial criteria to screen people, but put more stock in person-to-person evaluation. Others might immediately put your resume in the circular folder, but since email is pretty much free (other than your time) and most people want an emailed resume, it can't hurt to apply. Let me give a better example: You have two years of Project Management experience. The job calls for five years in the exact topsy turvy atmosphere in which you are currently working. Apply, anyway; in a perfect world, no one will have 5 years and they'll take anyone they can get. In an imperfect world, they may take a look, see you have the skills and take a chance.
Always have a targeted cover letter. I like to keep my cover letters to 1-2 paragraphs, tops. I look up the firm and the type of work they do, and I begin my cover letter with my interest and/or experience in that field. I highlight a few of my best qualifications, and end with "look forward to seeing you soon" or something equally "The-ball-is-in-your court, please-call-me, god-I-hope-I-don't-sound-desperate." Sometimes the only thing that causes them to click open your resume is a decent cover letter, and most people (at least in technology) send maybe a sentence (if that). You'll stand out. Just, you know, have your cover letter proofread, as well, before you send it, so you don't stand out in a bad way.
Ping again. I set an alarm in my calendar to email the address again in a week; if I've heard back, I cancel the reminder. If I haven't, I send another email asking if they got my materials. I typically don't ping more than the once, though, unless they've acted somewhat interested. A lot of people use silence as their method of explaining you didn't make the cut. However, a lot of people us silence when they really mean "Doh, overwhelmed!"
Basically, you want to be noticed by someone for a good reason, pass the screeners, and make sure that anyone who calls you back about a position/resume knows at least some of the experience you have in the area of the job. Applying for jobs can be pretty depressing, extremely overwhelming, and/or terribly exciting. I just try to manage the excitement a bit, so I can enjoy it more and panic less.