Some have become creative in "eye" control:

Seriously, I am left handed, but shoot rifles right handed, left eye dominant, slight adjustment on rifle but pistol is both eyes open.
The brain needs to find the eye that works for you and stick with it, even with both eyes open.
During rifle training in the Marines I was taught to focus on the front sight and center it on the blurry bulls eye.
+1
Try to align front sight with target as more of a reflex action than a focused "look". Like pointing your finger at someone. You don't have to "aim" your finger to get on target.