Correct method for invoicing

[M Prindle]

Hi everyone,

I need some help with GNUCash invoicing.  This is the 3rd month that 
I've created an invoice and totally messed it up when I get the payment 
for it.  I need a process flow after the invoice is created and posted.  
Here's what I know how to do so far.

1. Create an invoice for xyz customer for a job.
    What is the income account?  The account the money will be deposited in?

2. Invoice is posted

3. Payment is received.  I then open the invoices window and select 
Process payment. 

 From here on I'm pretty fuzzy.  The payment came in via paypal so I 
have to account for the paypal fee's also.

If someone could help me with the process flow and the accounts to use 
that would be wonderful

Thanks,

Mike