To export your data from QuickBooks, first open QuickBooks and find the "Excel" drop-down in the menu bar. From there you can choose what data you'd like to export (customers/vendors, lists, items, reports, etc.). Next in the export window you can choose to create a .CSV file, and then select "Export." From there you can name the .CSV file and save it on your computer wherever is most convenient for you.
Once saved, you can then use this .CSV file to import your QuickBooks data into Sage Accounting.
Sage Accounting is much easier to use than QuickBooks, and even learns how to categorize transactions quicker automatically the more you use it.