Send postcards to the House of Representatives (US) or the Prime Minister (UK), or anyone else you believe needs reminding of their humanity: demanding a ceasefire and demanding freedom for Palestine.
These are free PDF downloads, for you to print at home as many times as you wish to, adding stamps as you go. The are available in both colour and black & white versions, and a light-to-medium thickness card through a normal printer should work well in most cases.