how do you set a custom background like that?

these are my two favourites

[img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/377460/4abb77bff5133a6c0251f753cfc9b69870423b32.jpg[/img]

[img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/331510/f1c8a182f55786a662b04f8b77744bafe92f1ede.jpg[/img]

[img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/299460/0779ebb4bd7ab04f7858d8d0bb91f0de3ef2c958.jpg[/img]

[img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/297410/ce0f6919e67567796874b3c99405d4a667c16bbe.jpg[/img]

My collection might seem big, but they're all classily dope, believe me.

http://steamcommunity.com/market/listings/753/205910-All%20the%20tapes
http://steamcommunity.com/market/listings/753/205910-Rucksack%2C%20Goggles%20and%20Reality%20Boy
http://steamcommunity.com/market/listings/753/205910-The%20Dotties
http://steamcommunity.com/market/listings/753/328940-Family
http://steamcommunity.com/market/listings/753/347560-Moonlit
http://steamcommunity.com/market/listings/753/300540-The%20Sword
http://steamcommunity.com/market/listings/753/300540-Light%20in%20the%20Woods
http://steamcommunity.com/market/listings/753/40800-It's%20Raining%20Men
http://steamcommunity.com/market/listings/753/237760-Intake%20Icons
http://steamcommunity.com/market/listings/753/92800-Reactor%20Grid
http://steamcommunity.com/market/listings/753/248820-Wisp%20(Profile%20Background)
http://steamcommunity.com/market/listings/753/375770-Ultimate%20Machine
http://steamcommunity.com/market/listings/753/282440-Cyber%20Punk
http://steamcommunity.com/market/listings/753/620-Intro%20(Profile%20Background)
http://steamcommunity.com/market/listings/753/368180-Polyball
http://steamcommunity.com/market/listings/753/354240-The%20Face
http://steamcommunity.com/market/listings/753/263980-Out%20There%20Somewhere
http://steamcommunity.com/market/listings/753/384280-Eyes%20On%20Ninja
http://steamcommunity.com/market/listings/753/246110-The%20Pale%20Sea
http://steamcommunity.com/market/listings/753/269270-Belly%20of%20the%20Beast%20(Profile%20Background)
http://steamcommunity.com/market/listings/753/416080-Poseidon's%20Rage
http://steamcommunity.com/market/listings/753/225280-FMR%20-%20Rising%20Moon
http://steamcommunity.com/market/listings/753/346200-Promotional%20Art%20Background
http://steamcommunity.com/market/listings/753/339190-The%20Cleanup%20Brigades
http://steamcommunity.com/market/listings/753/219740-Sure%20Beats%20Darkness
http://steamcommunity.com/market/listings/753/305820-Swamp%20World
http://steamcommunity.com/market/listings/753/331440-bitDungeonII
http://steamcommunity.com/market/listings/753/332200-Skull
http://steamcommunity.com/market/listings/753/233150-Blimpfall
http://steamcommunity.com/market/listings/753/277680-Love%20and%20Hate
http://steamcommunity.com/market/listings/753/277680-Lazy%20Ones%20all%20around
http://steamcommunity.com/market/listings/753/219890-AC%20Shatter
http://steamcommunity.com/market/listings/753/207080-Phil%20(Profile%20Background)
http://steamcommunity.com/market/listings/753/229580-Dreamz

I should mention that almost all of them can fit in any budget and there is no space backgrounds.

[img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/219740/7439be4f1046a90b567a55a44e973d663f195884.png[/img]

[img]http://cdn.steamcommunity.com/economy/image/xb9tCpStSm9YRQdfwNR0aH3zp7vQ3UQvjIvURSQyPM8MtFrxzbEMfficG6HmtDricOa-qIWfBjeHhsldJTE9yAGwSbHTuR9_-cFXp__-JOU6s-f7xcJTcYzciRdueS7LVepJqdyyGCyr10yv6aJx8y21sK3Yywl60d6KHG5vItoK[/img]

[img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/204630/4e608bb088e6204b0fb7e5b798a7e08547f2927e.jpg[/img]

http://steamcommunity.com/id/yandere_/
best setup ive seen

Brens and thalashs ones are realy nice
http://steamcommunity.com/id/ThalashEEE/
http://steamcommunity.com/id/BrennonH/

[img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/357900/0aeae99889bf0a916b48b637438d8a8c1dfdf6d2.jpg[/img]

[img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/230820/f1ef031e4827c2a92d48b1c838b99bae7b48f486.jpg[/img]

I'm rather fond of this one, myself.

I like these two idk
[url=http://steamcommunity.com/market/listings/753/96100-Space%203][img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/96100/b634bae382254704dbbfa6568c1664df51f0f577.jpg[/img][/url]
[url=http://steamcommunity.com/market/listings/753/204360-Animal%20Orbs][img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/204360/3c1fa75b447ae42a610fb034478f5495dacdb222.jpg[/img][/url]

Simple and clean

[img]http://vignette4.wikia.nocookie.net/steamtradingcards/images/d/d8/LYNE_Background_Outlyne.jpg/revision/latest?cb=20140723062514[/img]

[url=http://steamcommunity.com/market/listings/753/454480-Artificial%20Maze%20BG1]this[/url]

[img]https://i.imgur.com/Fm3rsNQ.png[/img]

[img]http://cdn.akamai.steamstatic.com/steamcommunity/public/images/items/210770/306ee60b6d177d6ab57abb3982aaa5e86204edec.jpg[/img]
I really like this one. Been using it for a long time now