Now you want to copy and paste a few of these cylinders in a cluster. 3-5 is a good choice, but make sure they are in a group. Use CTRL-C to copy the current cylinder. Move it aside and then press CTRL-V and you'll notice that the new cylinder appears where the last cylinder was. You can do this as many times as you want. I'm sure you could also use the "Replicate/Scatter" command too, but I find this method alot easier.