1.choose a the color or design you like
2.choose a brand the best are (Corsair,coolermaster)
3.make sure the case have exhaust fans 2 or 3 at least 2 in the front 1 in back
4.(ventilation) its how air come in and out of the case throw
5. if the power supply is mounted up or down best down(some cases come with power supply)
6.how many front ports or usb 3.0 and if the case have led lights or remote control for it
7. if the case support liquid cooling
8. your budget if you want you can give me your case budget and ill give you some good options