That reactions.coalition site is incredible for visually seeing what’s required.
The best advice is to jump in with something small and start to build a small number. You’ll start to get a feel for how the materials are distributed over the different reaction levels and what quantities are required.
You’ll also get a new appreciation for all things fuel blocks 
Ignore the below if you don’t want to see a shameless plug:
[spoiler]
If you’re interested, I’m selling a complete breakdown of all manufacturable items in the game and the build list for each, which includes all the reactions required. Check out the link below for more info.
[/spoiler]