I would say learn proper proportions first, then you can stylise any way you want, but you will know exactly how to modify and break things in a way that looks right, rather than copying a certain style only.
I think you should also move away from this "tutorial mentality", which dA being dA is full of...and full of lots of rubbish ones to boot. Learning is not about following a set process, it's about developing and practicing in a way that increases your fundamental skills and knowledge.
Perspective.
Good resources
Scott Robertson: How to Draw book.
Ernest Norling: Perspective Made Easy (public domain, so can be found free online)
Loomis: Successful Drawing and Creative Illustration are both available free online (search for "save loomis"). They contain useful info on perspective as well. Get all his books, they are great.
Values
Muddycolors posts on value that are useful.
http://muddycolors.blogspot.co.nz/2012/0...cture.html
http://muddycolors.blogspot.co.nz/2012/1...nails.html
http://muddycolors.blogspot.co.nz/2015/0...ntrol.html
The way I learned values was to take master paintings with strong value compositions, desaturate them, and do a study of the desaturated painting. It is very useful to start with a restricted range of values say 3 to 4 like in the second link above to recreate the image. Then you can refine it further once you have the major compositions down by adding more values. I painted nothing but grayscale images for a month or two. No colour at all. It seemed to help a lot.
People will help you in the sketchbook thread with tips and stuff, if you ask in your posts. Also you can use the shoutbox. Sometimes it is quicker to get an answer that way! Good luck!