First, don't do the things that destroy community.
Next, read Art Of Community and WikiPatterns for wisdom, tips, and tricks from other communities.
Conduct your wiki activities according to the Leadership Code of Conduct. Help others, be nice.
Also communicate, a lot.
After that:
Ed Price MSFT edited Revision 3. Comment: Refined title, minor edits, and added "See Also" and "External Links" sections.
Ed Price MSFT edited Revision 5. Comment: Added "Things That Destroy Community" link.
Pronichkin edited Revision 6. Comment: Minor edit (text formatting, etc.)
Pronichkin edited Revision 7. Comment: Minor (removed double space char)
Ed Price MSFT edited Revision 9. Comment: Inserted horizontal lines.
yottun8 edited Revision 12. Comment: Added "Other Languages" and ja-JP link.
Horizon_Net edited Revision 16. Comment: added language tags
Luciano Lima [MVP] Brazil edited Revision 18. Comment: Update link Wiki: Como Construir uma Comunidade (pt-BR)
Dave A Gordon edited Revision 19. Comment: Corrected grammar - Find to Found in "After that section - Bullet 2"
Zoltán Horváth edited Revision 20. Comment: adding hu-HU version link, small HTML cleanup
Ed Price - MSFT edited Revision 23. Comment: Added link - Wiki: Governance and Guidelines Portal
Maheshkumar S Tiwari edited Revision 24. Comment: Added link in See also
Carsten Siemens edited Revision 25. Comment: Added German translation to section "Other Languages"
Thanks, so helpful.
Luciano Lima [MVP] Brazil edited Revision 14. Comment: Added link of the article Wiki: Como Construir uma Comunidade (pt-BR).
Ed Price - MSFT edited Revision 15. Comment: Added Spanish