(sorry about my English)
In my opinion there is no guides because there is no special glitches or etc. You just have to use SuperUltraMegaMicroskill and tonns of time to run Starcraft. Just look at WR vod to understand what you have to do and repeat it.
But I could be wrong.
There are no guides mainly because strats are not refined enough to the point when they cannot be improved (Remastered also patched many overused exploits like morphing mutas from zerglings etc).
If you want some help you better ask for it at RTS Speedrunning Discord where all active speedrunning legends are hanging out: https://discord.gg/zVXr9UKKBp
Generally if your going to start running any game either spend enough time to learn everything you can about it and try things out or if there is other videos and resources available then that means you can be lazier which is generally how things go these days. Seeing as SC is an RTS allot of the run besides going for the objectives is gonna be knowing how the games mechanics work like any game and then trying to capitalize on them. This will obviously require getting decent with skills such as micro-management of various units and tasks. You will learn actually a good amount from watching any number of the IL runs or even FG runs that are already available, but you won't understand much of it till you've played the game enough to know what is being done. So even if you had the resources you still need to build some experience and knowledge of your own first.
There is no guide not because there is no special glitches or no refined enough strats... (what are you guys saying lol) there is no guide just because the community is small and noone has put the effort to make one yet.
I will put here what i sent to Nilsi on discord, some resources that might help...
To check maps triggers: ScmDraft 2 (map editor) https://us.forums.blizzard.com/en/starcraft/t/scmdraft-2-alternative-starcraft-map-editor/153
Downloadable Original/Vanilla campaign maps https://www.speedrun.com/tools/Original_Campaign_red1l.rar
Downloadable Brood War campaign maps https://www.speedrun.com/tools/Brood_War_Campaign_8u5vq.rar
Usefull resources: Ingame cheats to test things out faster http://classic.battle.net/scc/pcheat.html
Glitches list (there is no unified and complete list as far as i know) https://kb.speeddemosarchive.com/StarCraft/Game_Mechanics_and_Glitches https://www.starcraftai.com/wiki/Tricks,_Glitches_and_Exploits https://liquipedia.net/starcraft/Bugs#Game_Bugs
If you want to play on older versions (not for Remastered): There is surely a better way of doing it but to make it work I installed the game using the original CD, not in the Program Files folder so you can still have Remastered installed and working properly.
Downloadable version changer (not for Remastered) https://www.speedrun.com/tools/SCV.Selector.Full.2011.03.24_a23bn.rar
Patches list https://starcraft.fandom.com/wiki/StarCraft_version_history
For basic game mechanics... go check liquidpedia or some videos on youtube I guess
As MASH said, watching IL and FG runs is a good way to learn.
