For example, let's say you want to set text to sentence case using formulas for the "Description" field.
What you need to do is to create a new field and apply this formula:
TOUPPERCASE(LEFT(A8, 1)) + TOLOWERCASE(RIGHT(A8, LEN(A8)-1))
You can replace A8 with the field you would like to reference.
After applying that formula, your new field will populate the sentence on the "Description" field on A8 with the first letter capitalized.