The SSD maker will often provide you the software to copy your partition to the SSD. You may want to run CCleaner or clear temp files and move out un-needed temp and personal files from the drive / partition before cloning over the drive so the partition will fit onto the new SSD. The instructions ideally will tell you the how-to's and what is needed.
You will also need to run some optimisations (sometimes taken care of by the SSD's softare) on the operating system for best SSD performance. It's basically disable defrag and enable trim. You also want the drive to be set up in the motherboard as AHCI rather than IDE mode. Depending on your setup, you may need to edit a registry key to allow AHCI on the newly cloned partition. If your HDD with windows 7 already is set to AHCI, it won't be an issue.