spotify premium required btw
download the files (search in this sub for links). will probably be zipped so make sure to extract them to whatever folder u want
go to spotify settings, scroll down to local files, make sure “show local files” is on. make sure the folder containing the music files is under the “show songs from” header, and the slider is on. if not, click “add a source” and add that folder
make a playlist, title it whatever.
go to the local files tab under “your library” in the sidebar. select all the songs and drop them in the relevant playlist
on your phone, make sure you are connected to the same wifi as your laptop. this is where most ppl fuck up. it also has to be a private network.
on your phone click on the playlist. if the playlist isnt there, close out of spotify, update, restart your phone, whatever
on your phone click on the download arrow on your playlist
if u did everything correct it should show up. if it doesnt, dm me and theres some steps i can show u to troubleshoot