PRISMA (the Preferred Reporting Items for Systematic Reviews and Meta-analyses) is 'an evidence-based minimum set of items for reporting in systematic reviews and meta-analyses.' The PRISMA checklist is a useful guideline of content that should be reported and included in the final write up of your systematic review, and will help when in the planning stages as well.
PRISMA-S is the reporting guidelines for systematic review search methods.
PRISMA-P is the reporting guidelines for protocols.
The EQUATOR Network lists reporting standards for multiple different types of study design. You can search for the right guideline for your type of study.
If you are undertaking a Cochrane review, please select the correct Cochrane Handbook for your review type.