that picture hella sucks. not too be rude but a better picture may help some of us diagnose it better!
it does look really bad and there are a couple of things i can suggest for this current plant and for future would be plants.
i would with the current plant, take a pair of Clean scissors and trim off the yellow/burnt looking parts of the leaves (not the entire leaf, unless the entire thing looks dead)
get rid of that diseased look so it doesnt spread any worse than it already has, increase your drainage by (if its planted in a pot) creating more drain holes, and also if it is in a pot, put that damn thing under a CFL light or something, the sun is too powerful for it.
with future grows, i would recommend purchasing a pre mixed potting soil suitable for cannabis, or buy the necessary ingredients to mix your own, i prefer to purchase a pre made soil-less potting mix that contains CoCo fiber, pearlite, and some sort of sand or granite like (
http://www.aquaserene.com/store/products.php?1804&manufacturers=1) or similar. Fox Farm Ocean Forrest is a very popular soil to grow in. and if your giving it any nutrients STOP! you don't or wont need to fertilize a seed until it gets about 4 true nodes.
keep in mind drainage is very important like i mentioned above. if you need help just ask people on this forum and you will get it!
remember to +rep if this helps