My first canvas

If you've not finished yet - you may be happy with this at the stage you've reached, and that'd be fine! - I suggest just a few sharper touches of detail, rather, perhaps, a bit of brush drawing just to help draw it all together. It can often help a lot, even if it does usually mean that you'll have to do even more work once you've done it: still, nothing ventured.... A little bit around the mouth, to show the division from the middle of the nose down to the mouth, a bow shape perhaps to show the line of that mouth (if it can be seen in your photo), and maybe blow that right cheek (to the left as we're looking at it) out a bit because he looks a bit as if he's sucking his cheek in. Mind you, he might be - 'starved, I am! Underfed.... don't ask much, just the odd bikkie, crisp or two, side of ham, half a pound of turkey breast, perhaps a whole salmon - just crumbs from the table..': I've known a few Labs: they'll eat until they chuck, and then come back for more, if you let 'em. If you want to leave it at this stage, mind, then do (isn't that kind of me?): you've broken the ice of a perishing difficult subject, and can come back to it in a new painting. The dog won't mind, one way or the other. 'Izzat me? Ace! Gotta bone, biscuit, and about that side of ham......?'