Vim panes resizing

You can maximize panes

  • Horizontally with Ctrl w |
  • Vertically with Ctrl w _

To make all panes equal type Ctrl w =. As resizing is a frequent
action, you can consider following mappings:

nnoremap <silent><Leader>+ :exe "resize " . (winheight(0) * 3/2)<CR>
nnoremap <silent><Leader>- :exe "resize " . (winheight(0) * 2/3)<CR>
nnoremap <silent><Leader>> :exe "vertical resize " . (winwidth(0) * 3/2)<CR>
nnoremap <silent><Leader>< :exe "vertical resize " . (winwidth(0) * 2/3)<CR>

Source

For maximizing and restoring the current window I suggest you trying vim-maximizer which toggles the current pane size with F3.