The resume writing service does not require knowing anything about you. All they ask you to do is fill out a standard online questionnaire and maybe submit your current resume. A competent service needs you to fill out a questionnaire; however it does not end with this. They contact you and ask for numerous other details about your career and achievements that they need to create an effective resume.
Avoid being vague If you have references include them. Dont say available upon request. If you have gaps in employment explain them clearly. They will probably come up in the interview anyways. Being prepared in advance by giving complete information in your resume is better than being caught off guard in the interview or worse skipped over all together.
Add in a list of skills Your resume is no place for modesty. Highlight your skills especially if they are specific to the job youre applying for and list where you gained experience with that skill set. Instead of being general give concrete details and highlights. For example list your experience with Microsoft Office or even a particular piece of software over computer skills. Make sure to include plenty of competency statements.
Be honest Never lie or stretch the truth on your resume. If your employer finds out later you will probably be terminated. If your resume is lacking in some areas build those areas up honestly by increasing your skills instead of pretending. The truth will always come out eventually and it usually hurts you in the end.
An attractive resume template/outline makes it more powerful. Just as dressing smartly helps a candidate in an interview good formatting does the same for a resume. Looks do matter at all places in the real world and on paper. When you present yourself well you get noticed. Similarly when you present a good resume it will be noticed; otherwise it would be very easily find a bin to rest in.