You can make utilities for yourself where you can put all your calculations and worksheets. This will reduce repetitive work to a great extent and help you save time for some other productive and constructive work. Apart from them, there are a countless number of other ways to use spreadsheet such as planning your tax, investment, cash flows, managing phone numbers and contact details and the like.
If you find creating financial spreadsheets a task that is a little to advanced for you, do not fear. There are other options for you that can combine and even exceed all the features even the most advanced personal finance spreadsheets can offer. The other options such as personal budget software may cost more than a spreadsheet you create at first, but are also powerful enough to pay for themselves with the advanced budgeting features they provide.