Like most things in life, all it takes is a little practice, followed by some more practice. When I start a new spreadsheet, I find it's helpful to ask myself "What in God's name am I trying to achieve with this time-sucking monstrosity"... and then go from there...
-I've had a student loan debt and payoff spreadsheet for 7 years, its helped me immensely, and began my "money management" process.
-Monthly Budget spreadsheet
-I have a net worth calculator, that includes year to year projections (as well as quarterly projections)
-I have a yearly Effective Tax Rate calculator
-Investments and Returns spreadsheet
It's great when you can connect your spreadsheets and have everything auto-update. Ends of saving hours and hours of time (on the back end, of course)
I'm weird, and find this stuff not only illuminating, but kinda fun. Best of luck to you, and ask specific questions here on this thread, and I'll be happy to answer.