When amateur volunteers just get on the plane in a quest to help, they instead end up interfering with the plans of professionals who are already there. I read about how the Kathmandu airport got super congested due to incoming goods and people that the actual movement of victims and help for them got affected. Such untrained people swarming there would only add up on those who have to be housed and fed, and this could disorient the efforts of the actual humanitarian societies for those who are in an actual need.
I also read about how certain packages with clothes were rejected and I think it makes sense. Someone who is bleeding would not do much out of a blanket or a cloth, he needs medical attention. And he needs such attention to reach unobstructed to him without being diverted due to another airplane carrying unwanted stuff.
So donate money as much as you can and do it right. Refrain from sending blankets, clothes and other physical goods, or the urge to go there by yourself.
Some useful links and references: