When I first started I had a terrible time with lefty shaving. Not only right handed but blind in my left eye. The awkward moves I went through were worthy of a you tube epic. It was a bit of a gong show to be sure. Turn your head so you can see the left side of your face in the mirror now look at where the razor is - oops wait ummmm cant see out that side - ok ok calm down - where the heck is the darn razor??? - get it where you can see it!! Wait wait my darn arm is in the way of my good eye - crud where are the band aids?
A couple of things I did.
One was to take a dead dull blade - one that couldn't cut me even if I tried. Lathered up and shaved off the lather just like when I used to shave with a bladeless safety razor next to my Dad. I concentrated just on figuring out how to get there from here. After several training wheels shaves I graduated to partial left hand shaving. Just the easy parts and then finished up with right hand or with a DE. I figured that whatever happened in the bathroom stayed in the bathroom so who would know I had cheated?
Gradually I found I was using the DE less and less and little moves that made it easier each time just naturally developed.
The other thing I did was shave - lots! Not only for practice but also to keep the beard growth down.
I found it a lot easier to handle the tricky parts if there was not much whisker growth. Just enough to hear the cutting. If that meant that a heavy beard would get a first pass with a DE then finished with a straight so be it.
Worked for me.