Making a sketch really helps. If you can draw well enough (I can't) you can use it to communicate with a client or a co-worker.
When you are using it to figure out something, though, all it needs to be is clear enough so you can read it yourself.
I made a few dozen sketches of Holocron ideas before I finally found the idea I was able to take through Inkscape, laser, and assembly of a prototype:
I made hundreds of sketches, mostly by hand but to-scale with the aid of graph paper, on how the thing assembled. But technical work is not the only place where a sketch is nice to clarify your thoughts:
And then there's this:
This is me trying to make any sort of sense of the Deep Time of the setting. The vertical axis more-or-less corresponds to time (logarithmically) and depth in the Earth (for some parts of the diagram). Essentially, the first Ancient culture was on Earth in the 2-200 MYA range, and among their other activities built Core Taps (essentially using a volcanic vent as a power source) -- many along the Ring of Fire.
Following the Wraith War (not to be confused with the Unknown Entity summoned up by Amanda's "Wraith Stone") a small number of Ancient survivors, now called Lanteans, come back to Earth. This is canonically at 10 KYA, which is problematic as the first Goa'uld (who later calls himself the Sun God, Ra) also canonically arrives on Earth about that time. One of them tinkers up the Asterion at Thera, built on top of the Core Tap there. If you look closely you might be able to make out a bull's head and a "clue" of thread in my scratchy diagram.
If I had the space, the diagram might have indicated things like the Elder Dryas, the first human migrations into the Americas, the Toba eruption, etc. There are a lot of odd things going on around that period! Canonically (according to the games this time), the surviving Lantean "triumvirate" on Earth breaks up, with Natla imprisoned in a stasis tube and Qualopec and Tihocan going off on solo careers as, eventually, mad old gods to early Central Americans and some sort of (possibly Mycenean) proto-greco-romans.
Roll forward to 3,000 BCE; Ra is overthrown, and the first historical Egyptian dynasties start up (no word on what the Assyrians or Sumerians thought about all this). Horus remains and is still wandering the Earth up through the Bronze Age collapse (witnessing the Thera eruption close-hand), at last getting stuck in a canopic jar sometime around the Amarna period of the Egyptian New Dynasty.
Some Lanteans may still be hanging around, whispering into Plato's ear (or perhaps Solon's). And to Iron Age "Celts," as well, giving rise to some of the Arthurian legend as well. Plus donating Excalibur, and continuing to use the Ring Transporter-like Travel Dias system established in various remote corners of the world (and possibly on others as well...wherever it is that some of the events of Tomb Raider: Underworld actually take place!) Others are off Earth, eventually either dying off or Ascending, but before that join for a time in a great league with the Asgard, the Nox, and the Furlings. The last have never been heard of since.
In 1945 the Trinity test frees Natla, who in due time seeks out and is successful in finding the three parts of the Atlantean Scion. Which is lost when another of the Ancient core taps blows up as did Thera, taking out Lost Island (which the games do not give a clear location for -- and as it is clearly either analog to or part of lost Atlantis, can be defensibly placed anywhere that amusingly mobile island-slash-continent has been placed by writers since Plato).
About this time the Stargate is being moved from Giza (having been uncovered in 1938), and Ernest Littlefield uses it in the post-war years. It is seen in a Federal storage facility outside of Washington in 1968, and finally fetches up at Cheyenne Mountain when Ernest's fiancé gets the program restarted. Of course we know what happens then!
And, no; not all of that is in the diagram. Mostly I have Lara, who has joined with unknown reason with psuedo-archaeologist Commander Newberry in his Landmaster-like "Ark III," (the diagram wrongly shows it with the funky tri-wheel arrangement) who may be stumbling on something Amanda left for them to find that may have something to do with the Ancient core taps that either Horus or Natla or the Asgard were investigating...
I think I've worked out my current plotting woes to the point where Amanda wrote a "Hello, Sweetie" message in some extremely obscure ancient tongue (possibly late-period Lantean) on the back of an artifact with equally obscure markings, which Newberry found and which attracted Lara to his dig in New Mexico. Amanda's message points towards Mount Shasta but also leads Lara into focus range of the Green Sun concentrator solar power plant -- which Natla Industries built, on properly previously leased by a wildcat drilling operation she blatantly named "Qualopec Oil Prospectors."
I did make one big mistake choosing Roswell as my starting point for the "Lara in the Midwest" chapters, though. White Sands, and most specifically the Trinity site, are a little too far away to properly explain whatever it was that Natla has been digging for in the Roswell area.