boot ‧ straps /ˈbuːtstræps/ BrE AmE noun [plural]
[ Date: 1900-2000 ; Origin: bootstrap 'piece of leather or cloth attached to the back of a boot to make it easier to pull on' (19-20 centuries) ]
pull/haul yourself up by your bootstraps to improve your position and get out of a difficult situation by your own efforts, without help from other people