Build a main bus
Run a set of parallel belts of core materials straight through your base and branch off them. A bus scales by adding length; a spaghetti base requires a rebuild every time demand doubles.
Leave more space than looks necessary
The most common regret is building too tightly. Space between production blocks allows belt routing and later expansion. Double your instinct.
Check the ratios in the info panel
The game shows crafting times and inputs for every recipe. Use them: if a machine consumes faster than a preceding machine produces, that line is already the bottleneck and adding more consumers will not help.
Power first, always
Production stops when power does. Expand generation before you expand consumption, and check the power graph after every large addition.
Automate science early
Research is gated by science packs, and hand-crafting them does not scale. Build automated production for each pack type as soon as it unlocks.
Defence scales with pollution
Enemy attacks are driven by pollution reaching nests. Expanding production increases attacks, so budget for defensive coverage at the same time as you expand.
Blueprint your own designs
Once you have a block that works, blueprint it. Reusing proven blocks is faster than redesigning and prevents subtle ratio mistakes.
There is no wrong way, only a slower one
A messy factory that produces is better than a perfect one you never finish. Rebuild only when the current one actually blocks you.