.tmux.conf

source /usr/share/powerline/bindings/tmux/powerline.conf
set -g mouse on

# remap prefix from 'C-b' to 'C-a'
unbind C-b
set-option -g prefix C-a
bind-key C-a send-prefix

# split panes using | and -
bind / split-window -h
bind - split-window -v
unbind '"'
unbind %

# reload config file (change file location to your the tmux.conf you want to use)
bind r source-file ~/.tmux.conf

# switch panes using Alt-arrow without prefix
bind -n M-Left select-pane -L
bind -n M-Right select-pane -R
bind -n M-Up select-pane -U
bind -n M-Down select-pane -D

Prerequisite
sudo apt-get install powerline