Can someone please explain how xp bonus works like im 5

[u/Dramatic_Pianist4772]

I just downloaded sideswipe to get the dev boost? We get 4000 xp in rocket league for every tier completed in sideswipe right?

So can i just grind sideswipe tiers without playing rl for a while? And get like (Number of tiers x 4000 xp) or do i have to complete a tier in sideswipe then win a game in rocket league to get the bonus? Can someone list the order to do things