Can't go past the Apple logo (Can't install El Capitan)

[FrankZap]

EDIT: I have now managed to go past the Apple logo.

Spent an hour going to the shop to buy a USB-mouse, apparently this was needed (why wasn't this mentioned in any of the guides?)... anyway, new problem:

When it says "Install OS", I can only choose the USB. None of my hard drives show up here.

What could be the issue?

I have set them to AHCI in bios. Do I need to format them perhaps? Got one 512gb SSD and one 6tb SATA.

Thanks

 

[Going Bald]

EDIT: I have now managed to go past the Apple logo.

Spent an hour going to the shop to buy a USB-mouse, apparently this was needed (why wasn't this mentioned in any of the guides?)... anyway, new problem:

When it says "Install OS", I can only choose the USB. None of my hard drives show up here.

What could be the issue?

I have set them to AHCI in bios. Do I need to format them perhaps? Got one 512gb SSD and one 6tb SATA.

Thanks

The hard drive will not show up until it has the OS installed on it. No OS on the drive = no icon at the Clover screen.