budgeting
The general budgetary advice is: don't buy.
Still, book-keeping is important when you share finances with family. We catalogue our expenses in real-time using notes on our phones or what have you, categorize them, and plug them into a nebu spreadsheet to make sure we stay within our means and help plan travels, etc.
This is the template I use for the spreadsheet:
,Rent/Util,Grocery,Car,Etc,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, ,,,,,,, 6200,b01:b30,c01:c30,d01:d30,e01:e30,b31:e31,a31:e31-,
The second, third, fourth, and fifth columns are used for expenses across different categories. The first, sixth, and seventh columns can be used to write notes (what bill or extraneous item the expense was for).
The last row is used for totals. Hardcode your income in the first column, and the total expenses for each column are tallied. The sixth and seventh columns represent total expenses and unspent income.