Noticed there's no tutorial in game so just adding it here:
W/A/D or top/left/right keyboard buttons to move and turn, Space to boost.(They have recently added an option to move by following mouse cursor, to select this option, in top right of main menu click "ABOUT" button and click on the cursor image)
Pick up good stuff like 2x powerup, blade and magnet, avoid stuff like direction swappers (grey arrows) and when got long enough better avoid boost powerups (red flame)
Spend coins you earn in games to increase buff duration.