How can I add Linux to my system with Windows 10 and El Capitan already running?

[Going Bald]

Thanks for ur suggestion StudioK. So if I got it right and from what I see from my own installation (X then WIN10 and then Mint all on the same drive), the way to boot now is through BIOS. If I want X or WIN I can choose them from Clover which is 1st on my sequence. If I want Mint I need to tell BIOS to boot from it straight away. Any idea how can I add Mint as an option to the clover loader? Tnx in advance

You do not have it installed properly if there is nu ubuntu folder in your EFI folder along with the apple and clover folders.

 

[mavenio]

You do not have it installed properly if there is nu ubuntu folder in your EFI folder along with the apple and clover folders.

My mistake. Linux folder was on EFI and for some reason I missed it. Thank u so much!

 

[Going Bald]

My mistake. Linux folder was on EFI and for some reason I missed it. Thank u so much!

You may need a custom entry in Clover as the poster here http://www.tonymacx86.com/threads/help-booting-systemd-arch-efi-with-clover.188191/ did. See post #3 for that member's solution.