This is one of those right tools for the job situation. You need a crimp tool that has the small sized crimper, like the one in this picture. With this tool, the smallest size slot is used for those kind of connectors. I bought this one a few years ago at radio shack for about $8. While a Radio Shack might be hard to find now, you might be able to buy the same kind of tool at Ace or Fry’s, or order from Amazon. Some wire strippers have a crimper, but usually not one small enough for these. Using a pair of pliers is also not a great idea, as you need the tool to guide the sides to fold back in on themselves.
Jumper wires will also work. But, “Teach a man to fish…”, right?? 
