You'll need at least 23,500 coins to purchase the items before you can use them in the game. They're located in The Stash under Clothing and Jetpacks.
Top Hat - 7,500 coins
Classy Suit - 6,000 coins
Traditional Jetpack - 10,000 coins
When you've purchased them, equip the items and reach 1000m (1km) in the game. To make things easier, you could spend another 1000 coins on a Head Start which will get you through 750m, leaving 250m left to achieve this.
Once you reach 1km, the achievement will unlock.