Before you start designing a brochure, decide how it is to be used. Are you going to use it as a self mailer? Are you going to mail it inside a business, #10 envelope with other materials? Are you going to leave it in a rack at a hotel or Visitor's Center or the like?
Is this going to be part of a presentation packet or seminar? In other words, what size does the finished piece need to be?
A typical tri-fold brochure could be 8.5 x 11 folded to 8.5 x 3.666, OR, you could make a simple 8.5 x 3.6 rack card, which would give you “3 Up” on an 8.5 x 11.
OR- do you need several 8.5 x 11 sheets in a binder, presentation folder, or spiral bound with a clear plastic front and solid back cover?
If you are working with a folded brochure, such as the 8.5 x 11 tri-fold, organize your material in “panels” - you will have 6. Remember the front panel is essentially your cover. This may be the only thing that anyone looks at- you want to entice them to go inside, but if they don't, you want to be sure the front panel relays the essence of what you are trying to convey. Also remember to leave room on the back panel for addressing, if this is to be a self mailer.
You can also simply collect the information, your logo art, any photos or art you specifically want to use, and give this to the graphic department of your print provider and have them format the brochure for the size you need. It may be easier for them to provide a professional looking piece that will print well on their equipment. Of course you will be proofing and giving feedback during this process. If you still want to create the brochure yourself, remember to provide a hard copy (if possible) as well as a PDF and the native file – just to be sure the print provider sees what you are seeing. Remember that different programs and different printers can often change color or create “glitches” between your file and the converted file the printer may need to create to produce your piece.
Lastly, don't forget your print provider may be able to provide mailing services. In which case they probably have a bulk mail indicia (if you don't) that they can print directly onto your piece. Be sure to included this discussion at the initial design stage and be clear what post office the mailing is going out of, so it matches the indicia.