First, you will have to describe what is the problem faced by your company, why it's seeking employee motivation. The current performance appraisal method followed. There is no format of effective performance appraisal as such, you have to make it effective and implement.
You can appraise people on the basis of their KRAs and behavioural competencies.
-- KRA will be their goals for the year (minimum goals can be 5 or 6)
-- Behavioural competency will measure their quality of work, job knowledge, initiative, delegation, discipline, interpersonal relations, team spirit etc. factors
The KRA will ensure they are meeting their work objectives and behavioural part will take care of their managerial aspects.
While you design an appraisal programme, hope the following points will help you -
- Formal or Informal method
- Whose performance
- Who are raters
- What problems
- How to solve
- What to evaluate
- When to evaluate
- What methods
If you search on this site, you will get number of postings on performance appraisal.
All the best !