I think it would be great if those of you who have been involved in 3D printing for a while could share your best tips. in hindsight. from issues you had and things you have learned.

Here are mine.
1. Makes changes via the Arduino firmware. disable chitchat in Marlin
2. PEI Bed OMG this stuff is awesome for adhesion
3. PetG filament.. forget ABS, or PLA. PEtG is the best.. doesn't warp, is strong, prints well, and is food safe
4. Bondtech Extruder.. awesome
5. Fan on Control board. on stepper drivers
6. Simplify3D made my life easier
7. Alum Bed with Borsilicate glass
8. Auto bed levelling is great once you get it tuned
9. Run from SD card. so many failures due to weird USb connectivity from PC
10. PID Heating for Bed, helps keep things consistant, not hard to implement

Please share your learnings