Play Longer Time Controls...
For many at the beginner-novice level, speed chess tends to be primarily an exercise in moving pieces around faster than your opponent while avoiding checkmate, in hopes that his/her clock runs out sooner than yours. Or being fortunate enough to be able to exploit your opponent’s blunders before they exploit yours.
There is little time to think about what you should be doing.
It makes sense that taking more time to think about what you should be doing would promote improvement in your chess skills.
An effective way to improve your chess is therefore to play mostly longer time controls, including "daily" chess, so you have time to think about what you should be doing.
This is not to suggest that you should necessarily play exclusively slow time controls or daily games, but they should be a significant percentage of your games, at least as much, if not more so than speed games which do almost nothing to promote an understanding of how to play the game well.
Here's what IM Jeremy Silman, well-known chess book author, has to say on the topic...
https://www.chess.com/article/view/longer-time-controls-are-more-instructive
And Dan Heisman, well-known chess teacher and chess book author…
https://web.archive.org/web/20140627052239/http:/www.chesscafe.com/text/heisman16.pdf
https://www.chess.com/blog/RussBell/dan-heisman-resources
and the experience of a FIDE Master...
https://www.chess.com/forum/view/general/how-blitz-and-bullet-rotted-my-brain-don-t-let-it-rot-yours
I am struggling to break 1100 in blitz, but played a rapid game today and narrowly won against someone with an established rating in the low 1300s. Should I switch to rapid (G/30) for a while while also studying puzzles, and then switch back to blitz? I did a quick google and read various opinions about how blitz doesn't help you improve "real" chess, but real chess skills conversely translate to blitz.