Write your formula using formula components.
- Add a function 
 You can type functions out by hand if you know which one you want to use, or- Make sure the cursor is in the formula editor 
- Then click Choose fields & functions > Select a function 
 This opens a pop-up window to browse, filter, and select formula functions. 
 
- Add literals or field references - Literals are surrounded by quotation marks 
- Field references are surrounded by brackets. 
 You can write fields out by hand, or- With the cursor in the formula editor, click Choose fields & functions. 
- Scroll to see all fields in the table. Click a field to add it to the formula. 
 
 
- Add operators - Follow operator precedence 
 
- Check for and resolve errors - How real time error checking works 
- Troubleshooting formulas 
 
- Edit any necessary formula field options 
 For example,- Change how numbers display 
- Set permissions 
 
- Save in the page bar