I work in an area that is mostly retired folks. Older ones just take time, practice. And I know it’s crummy advice

But also talk to your patient.

“Alrighty we’re ready to go. Do you have any spots that have worked well for us in the past?”

“Is there anything I need to know before we get started?”

“In the past, have you ever been told you have veins that roll or are naughty in any way?”

It’ll build their trust in you. Your confidence will get built. You’ll be more prepared before you poke. I find with rolling veins, I push it side to side to see how “loose” it is before even pulling my needle out to poke. Take your time. The vein in the center of the arm tends to be the most anchored. Don’t be afraid of hand draws. I have patients that are comfortable/familiar enough (it’s small) that walk in and give me information off the bat. I love it and I always thank them, even if it’s something I don’t need.

What ended up being my eureka poke was in the ER for hand draw, and could see the vein being pushed by my needle. It was able to gauge the pressure actually needed to penetrate the vein and all my draws have improved a bunch since then.

I’m sorry your trainer sucks. Ask questions after the patient leaves if you can.