How to nonverbaly signal a drafting proposition to fellow cyclist?
Yes.

There are a number of different ways to initiate a paceline via hand signals, but the most common one I've seen and used is to make a circle with an upwards pointed finger.

Watch Peter Sagan (white jersey, yellow/red helmet) do this in the following video.

                
            

He's joking in this situation, but note that his fellow sprinters all know that he's referring to starting a paceline, which is why Greipel (green jersey) checks the gap to the rest of the peloton.