You do not have to be a Scribe to start selling Glyphs. All it takes is some research and Addons. I use TSM for posting, but Auctionator is best for people who are new to Auction House Addons. Once you have it set up properly you can just go through the motions and the gold will start rolling in!
Check The Undermine Journal for current prices and buying rates. Make sure you look at the Glyph heat maps. They have all the information you need, but if they seem to confusing you can start by looking up individual Glyphs in the search bar. Let's compare two different Glyphs on my server.
(Data from TheUndermineJournal.com)
As you can see, the glyph on the left is selling for more than the one on the right. The Market Price is the current AH price of the item. The Mean is the average price it goes for over the last 2 weeks. The Standard Deviation shows how volatile the item is on the AH. If we look at Glyph of Scare Beast, you can see the SD is about 130g. That shows that the price ranges from (211+130) 341g to 81g (211-130), so it's definitely a good glyph to sell. Looking at the Glyph of Divine Favor, you can see the numbers are super low. I personally would not invest anything into it, so you shouldn't either. If anything on The Undermine Journal does not make sense, you can always click on the "Video Help" buttons for a detailed explanation!
Finding the Glyphs for cheap is doable in many different ways. Check the Auction House daily for good deals or find a Scribe to make them for you. You can see if he has cheap mats for sale, or buy some off the AH. Glyphs normally have a very high turnover rate since there's a new toon born every two seconds. Don't worry about making all the expensive Glyphs right away. Start off with a few and go from there.
Now that you know how to sell in the Glyph market, you are one step closer to being financially stable in WoW. What are you waiting for? Go make some gold!