Hi ayiraheart. Thanks for clarifying your goals for me. I see what you mean about wanting to attach your receipts to expenses, rather than invoices. Don't worry, you'll be able to do this easily. 

The steps actually work the same way as James provided above, but rather than uploading your attachments to an invoice, you'd upload them to an expense. If you're trying to use the Receipt Scanning  feature and your receipt is too long to capture, this is the best way to ensure your receipt is still stored digitally. 

I hope this helps clarify things for you. If you're still unsure how to move forward, don't hesitate to reach back out. 

Cheers!