Alright, so lately I’ve been trying to find glyphs for portals, but my largest issues were actually finding the trading posts. However I have found a method that’s worked for me. There’s probably a better way, and if there is, PLEASE tell me.
My method involves the mission person in the trading posts. If you browse through the missions available, you can find ones where you have to “collect an item”. All you have to do is gather plutonium or something and it tells you to drop it off at a trading post. Thankfully, it marks it on your HUD. That’s how I found my first glyph, and I’m working on my second so I can travel to that one planet and collect the rest.