Embr (UP)

Whilst the other achievement guides are correct, it's much simpler.

You need to unlock and equip a ladder before playing online anyway so do this, then simply lean a ladder against the board and drop it in. The ball is either underneath the board, or to the side depending which one you use.

This way there is no luck involved!

In the multiplayer lobbies you can pick up a basketball and shoot at the basket with the button. However, I found it far easier to save up some money and buy the "Baseball hat" it allows you to doublejump.

With this you can stand underneath the basketball hoop and double jump up and then press the button to let go of the Basketball, it will drop into the hoop and unlock the achievement.

Note you don't actually need someone else in the lobby to get this achievement, simply load up a multiplayer lobby and you can earn this.
Good Hunting
-McClain

There are some good ways to do this achievement on here, however I didn't see anyone put this which is the way I did it, wasn't sure if it would register but some games in the past have and this way does work on Embr as well.

Simply go onto multiplayer, press up until you are selecting the type of lobby visibility you want (Private/Unlisted/Public) I did mine on private.
Select a random load of letters for the lobby password as it does not matter for this. Finally press "create crew"

now you have to find the basketball somewhere in the car park, it is quite big really so shouldn't take too long to find. Also now go and find the basketball hoop.

Once you have found both, all you have to do is stand underneath the hoop and look up through the hoop, press to throw the ball up, and hopefully it comes back through and pops for you, If it doesn't fall through the hoop slightly adjust your angle of stand compared to the hoop and try again. Mine took me about 4 attempts to get the right angle of standing for it to fall back in.

Hope this helps people