Getting sesame seeds to stick to your seared fish
i just stick the raw / marinated fish into a plate with the sesame seeds -- press down a little and flip. then i just fry the fish in a medium/high heat stainless pan. i use a smallish pan (maybe 8-9 inches). i use mix b/w spray oil and regular so the bottom is fully covered. i've never had a problem with the seeds sticking -- not to say they don't stick at all - but usually the majority of the seeds stay on the fish.
You can use a little olive oil but I've used an infused mayo that works great. I've done this with sesame seeds and panko crumbs. The last one I did was a wasabi mayo that I slathered on a nice piece of tuna then rolled in panko and browned in a pan on the stove to just get color/crust on the outside and keep the inside raw. The mayo melts away but really helps the coating stick.