And as for the paper towel tip, I already use that to attempt to correct mistakes. If I paint something wrong it's my immediate instinct to grab a tissue to rub off the paint - even if it doesn't always work. Thanks for the help though.
I only realised the arm was off just after I started painting..... I never start painting until I've got the pencil outline perfect but stuff always seems to slip through the cracks. Not much I can do about it now I suppose.
And btw, it isn't really my piece, it's a copy of one I listed off Google images. I do this a lot in my projects to help build confidence for when I can start sketching out my own detailed profiles of people. But I have to say, I've still got a while to go yet before I can confidently draw Samus from scratch of my own accord.
And also, your painting looks amazing. Did you do those grapes too?