See the screenshot of how I have vim configured below. The \'gutter\' i.e. where the \'+\' and \'~\' symbols appear show my git status using this amazing sublime text port for
Another option that hasn't been mentioned is to eliminate the sign column entirely and put the signs into the number column.
Adding this to your ~/.vimrc
set signcolumn=number
produces
(this is using custom symbols with the Ale plugin in iterm Vim).
This is available in "full" Vim versions 7.4.2201 or newer that include the +signs
feature (I use the version installed by Homebrew on MacOS).