If there's something you really desperately want, and you're just a few bucks short, rather than spending more time doing various tasks to earn them, the quicker option may be to purchase some outright. Thankfully, we offer the option to do just that.
By clicking the bucks icon in your top left corner, it will lead you to the bucks purchasing page.
There is also an alternative route to get to the same page.
Click "Shop" on the left hand bar, and this will direct you to the general Robux shop.
You will then see the "Buy Bucks" tab, and through clicking this will also lead you to the bucks purchasing page.
Select which Bucks package you require, and continue following the instructions given by Roblox for purchasing the bucks with Robux.
If you don't have enough Robux, you can follow Roblox's on screen instructions, or head here to buy some more.
If you're playing on Xbox, check out this article, and for PlayStation, check out this article.
Once done, you'll see that your Bucks total has gone up and you can spend your bucks how you wish!