I just installed the loki os and its amazing. I love it...I had some problems with all the repositories about adding elementary tweaks and its okey now...I solved it but please,please tell me how can i install a darker theme. I tried just like I said adding all the different repos that i read about on the communuties but none of them are usefull. It allways gives me the same answer "unable to locate!" Help?
You have to go in the "Appearance" section of elementary tweaks, and look for the swithc next to "prefer dark theme".
I've used it but some icons (eg. in scratch) hare hardly seeable, so i go for the default theme. i've tryed also some gtk3 themes from gnomelook.org but mostly are not fully compatible with eOS, the desktop will be messed up.
Edit: Sry, to better answer you question; the easiest way to install a dark theme (and themes in generale) is to create a hidden folder in your home named
.themes (too actually see it in files you have to press ctrl +h) and unzip theme folder(s) in there.
Then you have to download GTK3 themes, good sources are Deviantart and gnome look.org, but as i wrote before there are still a few themes fully compatible with eOS. The old and outdated elementary os update PPA had some however:
You could install a tweak: https://github.com/elementary-tweaks/elementary-tweaks#elementary-tweaks
'Tweaks' appears in 'System settings'
Or you could use dconf-editor to directly change values