It is highly recommended that everyone keep at least one backup of their wallet. To backup your wallet, follow the listed steps.
1. Insert an external hard drive/flash drive into your computer
2. Navigate to your wallet
3. Click on File, then Backup Wallet
4. Name the file "wallet" and keep the extension the same
5. Save the file to your external hard drive/flash drive
6. Now, if you computer crashes or something else happens, you can just move the wallet.dat file into a blitz roaming folder, and you will have access to your coins.