How to create invoice shortly to One or two steps

Hi,
How to create invoice shortly to One or two steps?
Thanks.

Hi Musahid,

You need give more details if you want an answer to such a question.
What do you mean by steps ? Presently, an invoice is created in 2 steps, but has confirmation dialogs. For this you may want to evaluate the attractive module from @ksar Module : Remove Confirmation Pop-up
Then, it really depends where you come from : do you have to fill in all products/services, do you have an associated order/proposal ?
Regards,
Marc