on desktop or mac, go to spotify and open the playlist you want to insert, and then click on the three dots “…”, share, and then “embed playlist”. it should pop up with a customization menu where you can change the color, height, width, compactness, etc. after you’re done, click copy and paste it to your spacehey profile under the “about me” section. make sure you’ve included the link between the <style></style> tags or else it won’t work.
if you’re on mobile, you can retrieve your embedded link by going to your spotify app, clicking on the playlist and three dots, “copy link” and then going to https://iframely.com/try where it will create one for you and you can customize it, then copy and paste it to your profile.
hope this helps ^.^