Restart the system and press the Option key so you can select the SSD as the boot up drive. Once done you'll want to double check if it's working correctly. Run the installer selecting the SSD drive it will install a fresh OS onto your SSD. The next step is to download from the Apps Store the OS installer. With the SSD plugged in to your system you'll need to run Disk Utility to partition the drive with GUID and format it with Mac OS Extended (Journaled) partition. Here's one unit: Startech 2.5' SATA to USB adapter for 2.5' drives. You'll need to get a SATA to USB adapter so you can connect your SSD externally to your system. Mavericks and newer OS's have firmware updaters within the OS installer.

Hint: the last digits (after the last dot) are hexadecimal so you'll need to convert it to decimal to know if your systems version is newer or older than the T/N.

You might have something still newer depending on your OS version.

Follow this Apple T/N: About EFI and SMC firmware updates for Intel-based Mac computers.

First thing I would do here is make sure your systems firmware is upto date.

Old Snook for mac instal