First - realize that you are not a pariah here - everyone has this problem. You are not a horrible drain on society for occasionally asking for a favor, and there's a certain balance of "pay it forward" here where people who have had good working relationships help each other out.
Realize the difference in types of references:
Employment verification - is simply that you have worked where you claimed, under the circumstances you claimed (job title, length of time, office location, major division). Often companies provide a phone service for this, so that managers won't have to be the contact point every time a verification is needed.
Professional reference (phone) - is a more targeted personal expenditure of time on behalf of someone who was a good colleague/employee. For the referrer, this means committing one's phone number being shared, and to be ready to make time for a call and to say some meaningful, true, nice things about the person asking for a reference. Usually the commitment is a 1/2 hour to coordinate the call and a 1/2 hour to provide the verbal reference.
Written reference - is a written form of the professional reference. It's even easier, because you can write it once, and expect that the person requesting it will keep it on file so you don't have to re-write it every time.
Many jobs will want ~3 references, of your choice, at least one from a former manager. They may want an employment verification from every job listed on your resume. So... if you've had 20 jobs, you still really only need 3-5 people who are willing to be your reference... you need 20 employment referral contact points.
Have a Reference Pool
- Make note of people (bosses and colleagues) who you liked and would work with again.
- Tell them so, especially when you leave a job. "Hey, it's really been a pleasure working with you... may I get your information and keep in touch?". Exiting a company is a great time to ask others if they are willing to be a reference in the future. If you've just taken a new job, you don't need a reference right away, but you can always ask "in the future, would you mind me asking you for a reference?".
- Actually keep in touch with former coworkers. 1-2 times a year is fine. Grab lunch, write a "hello" email. Ask how they are.
- With steps 1-3 in place, it's much less awkward to ask "hey, how's it going? I have XYZ job opportunity, could I ask you to be a reference?" - now you aren't calling out of the blue, this is a relationship.
When asking, make the process as easy for the person helping you as possible. I recommend that when you ask for a reference you give as much detail as possible. For example:
- Nature of your job search - "My current company is doing poorly, I hope to find something in the next few months". or... "I'm doing fine, I'm just looking for something better." - that tells the reviewer how urgent your search is.
- Nature of the job you are looking for - "I'm trying to go for a sales position, as you know, I've got engineering skills, but I need to convince these folks I'm also a good communicator"
- Details of the specific reference they are giving - the job description, the name of the company, the timeline - asking early for an open ended reference is fine, but when you're actually giving out the person's name, tell them where and for what.
- Your details - send them a resume so they know how you've sold yourself. Don't ever ask a reference to be untruthful - if they point out inaccuracies in your resume, be willing to consider an update.
- Any connection info you can give - the name of the recruiter, the way they will contact your reference (they asked me for an email... so I assume they'll write you at this account)
That way the person helping you is prepared to be the best reference they can be.
- Keep your pool fresh. Some relationships will last a career and both people will feel they've benefited. Others go stale and are replaced with new relationships. Every year, review your pool and figure out whether other people in your life today would be a better fit than the folks who have agreed in the past to help you.
Helping is helpful.
As a manager I can tell you that being part of reference pools in my professional network is never a bad thing. I get a few major benefits out of it:
I keep in touch with people I liked working with... I change companies and grow in my profession. Having former employees of mine reach out on occasion can lead to me recruiting them to come work for me again. Having a formerly good employee come to work for me again is WAY less risky than hiring someone who I just met.
I use the kindness of referrers myself when making hiring decisions - if other managers weren't willing to give genuine references, then I would be stuck when trying to figure out my own hiring decisions. I'm not just doing good for my own network when I give a reference, I'm paying my dues to stressed out managers everywhere, who help me out when I need to check references.
Everyone asks someone else for references. It's like a potluck - everyone brings something, everyone partakes. You are only selfish if you don't help others in return. Your manager will ask their manager for a reference, and so the cycle continues.
When to be concerned about asking for a reference:
Primarily, when you don't have a good relationship with the person you are asking. If you're leaving because you've gotten horrible feedback or because you really hate your boss... this is not a good reference for you.
The other case would be if you must ask for reference giving that is over and above the call of duty. My experience has been that when I agree to give a reference for a job hunt, I may actually be used as a reference 3-5 times per person per hunt. Of those 3-5 times, I may get an actual call once. References are not checked all that often. In my industry, most folks don't hunt for a job every year - it's usually around 3 years before a person will ask again for a reference from me.
If you are going to be hunting in a way that makes the frequency of reference giving far higher than the norm in your industry - let the referrer know and be very thankful. Be aware that you may have to build a bigger pool so you aren't asking the same people too often.