JD's idea of using a proxy server is good too; https://www.hidemyass.com/how-it-works putting a buffer between your machine and wherever you log into. There's lists of "free" ones online but I've never used a proxy other than occasionally when I've been "asked" by a site if I wanted to. I just make sure I am as aware as possible of my surroundings/the businesses whose sites I use, what could happen, etc. Sure, bad guys can hack "anything" but the likelihood of their choosing me/my machine in a way that will affect me/I'll know, is not that great/likely given both who I am and the level of security I have in place for myself.