You can split your terminal with tmux. But these pane sizes are not same when you split more than 3 panes. This is not good to see and even might be obstacle for development. You can split equally size panes with only below two lines.

# split -v S
unbind S
## bind S split-window <- this is an original line.
bind S split-window \; select-layout even-vertical

# split vertically
unbind |
## bind | split-window <- this is an original line.
bind | split-window -h \; select-layout even-horizontal

splits

This is easy way!