A good reference writer:
Make a list of potential reference writers – faculty, staff, supervisors, employers - and narrow it as you narrow your search. Try to match each reference writer to the individual programs.
Let your reference writers know way ahead of deadlines that you will be applying to graduate school and ask them if they would be willing to write a letter in support of your application. Be aware that your reference writers may not always be reachable whenever you need them (sabbatical, academic seminars, vacations, etc.).
Supply your reference writer with all the information they need to write a strong recommendation:
The majority of graduate programs will ask for confidential references. This means that you have waived your right to review the letter of recommendation. Make sure you are comfortable with the people you choose to write your letters and this will not be a problem. If you are hesitant about what someone will write about you, perhaps you should choose another person.
Send the requested number of references to each graduate program. Don’t send too few recommendations. Make sure the letters are on the forms provided by the school. Don’t substitute other information in lieu of a letter of recommendation without checking with the admissions committee.