With 2021 ending soon, this is what I've learned from playing this game since launch.

-You can hit your interact key to pick up spike from a further distance. No need to always walk over it-Use drop key instead of looking down to pick up a new gun so it doesn't mess up your crosshair placement
-Experiment with where you are facing when you plant spike. Use the different diffuse angles and ranges to your advantage in post plant-Use the map for crosshair placements. Many boxes and lines on the map will be head height so line your crosshair up with those various map details.
-Put smokes IN doorways and learn common one ways
-Play off contact with your teammates
-DONT ego peek everything-When you jump peek or jiggle, even if you don't see them, look on your minimap for a little red question mark that will show if even a pixel of the enemy shows
-Pre-fire angles that you think that people will hide in
-Don't auto-lock then ask for people to fill roles for you
-Duelists don't have to top frag to be useful, they're there to take space
-Bunny hopping can be a useful skill to learn but remember that running in a straight line will almost always be faster
-Try and play like PROD for maximum game enjoyment
LMK if there are any that I miss!