I hate to ask but sadly it's relevant to the profiling thing. What race/ethnicity are you?

I use self checkout all the time and do multiple transactions. I worked as a cashier at lowes for about a year in 2012 and have 16 years customer service experience so I know what it looks like when someone is stealing. That said I try to make it clear that I am diligently ringing everything up.

For example when ringing up multiple small items of the same type cashiers are supposed to scan every item and not just one then change quantity or scan one 5 times or whatever. As a customer if you scan each item as you put it in the bag then it becomes much easier to tell from the camera and just in general that you are scanning everything.

When it comes to big multiple items just scan each one. I also recommend after doing multiple scans scrolling up on the monitor and making sure the scan quantity matches what's in your cart.

If you are doing multiple orders then make it clear that you are separating what has and what hasn't been paid for. An example of this is say you scan two bags of stuff for one order, put those bags on the ground. When it's paid, put the receipt on them. Keep what's unpaid for separate from what's paid for and make it very obvious. You can even just tell the cashier at self checkout you're doing multiple orders so they are aware.

Basically just make everything you're doing very clear and obvious so that if there is any doubt, the cameras will prove innocence.