1. Don't say you have 30 years of experience and leave a 27 year gap on your resume.
1b. Make sure you clearly delineate between each position you've held. Bolding the years worked, company, and title for two positions and not doing it for two others makes it look like there's a 27 year gap when in fact, it was just poor typesetting (see 7 below too).
2. Don't say you have 18 years experience as a Unix Administrator when you mean your home computer. (We interviewed this guy. He might have been at Junior Admin skill level except of course that his interview skills, attitude particularly, need lots of work. Hand waving away our technical questions as unimportant is the best way to not get the job. If they weren't important, we wouldn't be asking them.)
3. Include training, awards, and a goal with your 1 1/2 page resume.
4. Expand a little on the work you did at your other jobs. Providing a bullet listing of products and hardware without details doesn't impress me with your ability to summarize.
5. Don't fill out your work history with incomprehensible industry acronyms and jargon. If I have to look up what work you did more than a few times, I'm likely to move on to the next resume.
6. Write your resume with an eye towards the job you want. I assume when you fill out your resume with information on large multi-million dollar projects you've managed to completion and large teams that you've managed, that you're interested in similar work. So my lowly mid-level Unix Admin position probably isn't going to be a good fit.
6b. If your resume has several references to Microsoft Windows products in relation to your work history and two words (UNIX and Linux) but no details, I'm going to assume the resume is from a recruiter and that you're not really interested in working as a Unix Admin.
6c. If your resume has several references to security processes with a distant (10 years back) history of Unix Administration, I'm again likely to think this is from a recruiter and that you're not seriously looking for a Unix Position.
7. Have someone proofread your resume. Reading your work history and seeing the same four lines repeated is just funny. That the four lines reference Microsoft Gold disk and Microsoft MSAT makes it that much more humorous when applying for a Unix Admin position.
8. If you used to work here and left on bad terms, please don't reapply. We do remember and we'll just file your resume in the circular file after much reminiscing and laughter.
Just so folks know. By the time resumes get into our hands for review (we do the technical interviews), it's been through two or three groups. Someone thinks it's worth our time to review and decide. So I don't hold typos and things like multiple duplicated lines against the person applying for the job. I make every effort to look at the resume to see if the skills listed match the position we're offering.
Thanks for listening...
Carl