If the reminders that you need are for dates coming in the future, you can do this:
I use an Excel sheet as a reminder for when events are approaching. In the first row, I have cell C1 with today's date. It updates itself to the current day. The formula for this is =NOW()
A couple of columns over in the same row, I have cell H1 that tells me the date 60 days from now. The formula for this is =SUM(C1+60)
Below this, I have a list of my events in column B and a list of the corresponding actions that I need to take in columns C, D and E. In column F, I have the date that the task needs to be done by.
For each of the dates in column F, I set Conditional Formatting to change the date to Bold Red when it gets to be inside of the date in H1. To set Conditional Formatting, go to the Format menu and choose Conditional Formatting. On the Conditional Formatting dialog box that pops up, I have the first box as "Cell Value Is", the second box as "less than", and the third box as "=$H$1". Then just click the Format button and choose a Font Style of "Bold" and set the Color to Red.
The end result here is that the dates of my actions show in bold red when their due dates is withing 60 days of the current date.