You're aware of the hurdles you face which helps, I like to double, triple, quadruple check if need be.
I know stress makes it worse for me as well as lack of sleep.
With word mix-ups, it can help to add association dimensions to more clearly define them. Like with left and right, it helps to not just see the word but feel it. Making it multisensory to define and differentiate it may help.
Another one that I slip up on is Marshmellow, and Mushroom; I like to picture a colored mushroom as opposed to white one in association to the word as it makes it more different from that other soft edible thing(marshmellow).
unless my mind being prepared wats going on to be teach or i rely heavily on book to further my studies
I do too. It's really hard to mentally "shift" gears. To pass through school, I studied everything one month in advanced, you may not have to, the trick is finding out what works for you and making the appropriate compensations.
It's extra work, but you can do it!