Backing up an SSD is the same as an HDD.
What type of backup are you looking for? A full system image? Software/Programs? Documents?
At any rate I use Clonezilla as it is free and backs up exactly what I need and saves it to an image file that I can store in Iron Mountain.
I use Tuxboot which will download and install a bootable partition to a USB drive if you have one around.
You can Google "How to use Clonezilla" and you will find clear and concise guides to backing up your data.
You will need a secondary storage equal to or greater than your HDD you are backing up.
You can compress the image to save space for storing backups at different times. You can backup individual partitions or a full disk image.
Best of luck!