The best that can be done is the sending of weapons and ammo directly to Ukraine which are en route. Poland has sent weapons and supplies, and I just read that Germany "has agreed to the supply of 400 German-made rocket propelled grenades to Ukraine via the Netherlands, along with 14 armored personnel carriers, as well as 1000 anti-tank weapons and 500 Stinger missiles. It will also supply 10,000 tonnes of fuel via Poland."