Installing SSD using time machine & external hard drive I am wondering if someone could help me with the following:

I have a 15" macbook pro late 2011 and I am trying to find a way of changing to an SSD. I have backed up my machine using time machine onto an external usb hard drive. I am wondering if the next step is to install the SSD into the laptop OR if there is a step required so that I can install the operating system (or will I be able to install it when I switch on the machine for the first time with the SSD installed and then restore my files via the external hard drive?). 

I am able to to find lots of tutorials but they all seem to use a USB cable connected to the new SSD which I do not have.

Any help would be good, thanks!
If you have an internet connection you can just install the SSD, then boot the mac on holding CMD+R to get to the internet recovery screen from here you should be able to select time machine backup and just follow the steps.