Select all the due dates, use Format/Conditional Formatting, change Cell
Value is to Formula Is, enter
=A2+30TODAY() (assumes A2 is the active cell -- substitute as appropriate)
then click the Format button and assign one color, click OK, click Add,
change Cell Value is to Formula Is, enter
=A2+90TODAY(), click Format, assign a different color, OK your way out...

"tbird333" wrote:

I am making a spreadsheet for upcoming training and it due dates. i am
trying to set it up where when training is complete you enter the date and
time, and then when it comes withing 3 month of being due again it changes
color, and then at one month it changes again. I am having a hard time
finding the rule/formula to make this work