1. Be absolutely clear about the primary purpose and audience of the plan from the outset. If the plan has to serve multiple purposes, consider producing tailored versions (or tailored summaries).
2. Allow enough time to produce revised drafts of the plan – three/five drafts would not be unusual.
3. Write the Introduction, Summary and Conclusion of the plan only after the plan’s main parts have been finalized.
4. At an early stage, make some high-level sales and financial projections (covering 1-3 years) to explore the general direction and size of the business, likely viability and possible funding amounts and mix. For this purpose, consider using the Quik-Plan facility within Exl-Plan, our range of financial planners for use with Excel.
5. If the elapsed time needed to prepare the plan and commence its execution is lengthy, set the start date for financial projection close to the commencement of execution. For example, if you begin preparing a plan in January and hope to raise startup finance by October, the start date for projections might be set to September. Any expenses incurred before this date could be rolled up into the opening balance sheet for the projections.
6. Seek external assistance sooner rather than later. This may take the form of software tools, consultancy assistance in the form of specific assignments, or mentoring and counseling on an as required basis.
7. If planning a significant business, ensure that a management team has been identified (and possibly in place) before the plan is finalized.
8. Identify and cultivate possible key recipients of the plan during the plan’s preparation. This will ensure that when the plan is finally presented, these contacts will have some prior knowledge of its contents and the promoters and, where appropriate, the views of contacts may have been taken into account during the preparation process.
9. Start compiling the plan at the sections devoted to market research/analysis and sales forecasts/plans, or with details of the proposed product/service offerings. Leave the detailed financial projections aside until all details in relation to sales, costs, expenses, operations, capital investment and possible sources/types of finance have been resolved.
Source:http://www.planware.org/businessplan.htm#4