Hey Mark,
Open your time of sales. I usually like to plot the price and size only. Time is irrelevant.
Im assuming you use Tradestation. Right click on the time of sales and go to => Format Symbol.
In the section "Display" you should see a menu and check boxes. Set it to show trades >= 10. This should then give you a column for only 10-lots and above. I like to use two columns for the tape. The first one showing all trades and the second column showing 10-lots and above. This gives you an idea of the little guys vs big guys.
"Respect Your Enemy"
A 80-lot YM trader deserves a little respect don't you think?
See attachment of price action after the 80lot trader.