When you get many splits going in tmux sometimes its time for a new layout. There are four layout strategies that I use, main-vertical, main-horizontal, even-vertical, even-horizontal. Almost always I am useing the main ones with mod plus a or mod plus shift a keybindings.

# Select Layouts
bind -n M-a select-layout main-vertical
bind -n M-A select-layout main-horizontal
bind -n M-E select-layout even-vertical
bind -n M-V select-layout even-horizontal


for more information on how I navigate tmux, check out this full post