Here's what I'd do if I had laid claim to land that was already granted to me illegally (see Balfour Declaration, Haavara Agreement):
Don't ever be the aggressor in any case, invest only in strong defenses. Don't expand your country's borders further via settler colonialism by burning down and shooting at people who currently live on that land.
Don't force native people into open air prisons under Apartheid. Don't run an international assassination and terror squad under the guise of a foreign intelligence service.
Don't put "post future land grab Greater Israel" patches on your soldiers uniforms
Don't commit genocides. Don't shoot at starving people seeking foreign aid provided post genocide.
Don't have your officials publicly declare the previous inhabitants to be subhuman animals that must be eradicated.
Don't run to the big brother (that you control via blackmail, monetary influence, religious zealots) after provoking the wrong enemy.
I could go on.