Depends on what activities your company/organisation are engaged in but briefly :
- Newsletter should be anything from 4-8 pages (A3 x1 or A3 x2) for a monthly newsletter- some go as high as 12-16 for a bi-monthly one (every two months - not to be confused with semi-monthly)
- You need to decide why you want a newsletter and who will be its readers (is it internal staff news, is it meant for suppliers, customers, etc)
- Once you decide that it will inform what content you carry in it.
- You need a masthead with the company colours that makes the newsletter name (and resonates with the corporate identity so people know immediately who publishes it)
- Cover page should usually be a main feature (which can be continued on page 3 or 5 etc) - just like a newspaper.
- Cover page can also have a table of contents so readers know what else is there
- page 2 to 6 can be other feature - maybe focus on x, case study of y, best practices in z, etc.
- One good idea is to get other staff involved in contributing articles depending on their expertise areas and what the objective of the newsletter is
- Other content can include features on staff, promotions, new products, services, innovation (again think of what the objective of the newsletter is)
- Its also good maybe to have some humour section (jokes, amusing real life stories, ) puzzles, etc - basically leave these for the last page or so - and they must be regular (think of Friday nation - the crossword and puzzles page).
Thats all i can think of right now.
One last thing - you should also consider is an HTML based or PDF newsletter that you can email to clients - save printing costs - get your news out there pronto.
HTH