Good tutorial. It could be added, that this wallet generator can also be used to create Brainwallets, an even more secure way to store your coins.
Brainwallets generate your private keys from a (strong!) passphrase. Chose a passphrase that you can remember but that also can't be cracked easily.
A longer sentence of random words like "Correct Horse, Battery Staple!" (see xkcd comic https://xkcd.com/936/) with punctuation, maybe additional numbers ("10th Correct Horse, Battery Staple!" - be creative!) gives a good and strong password that's also easy to remember but hard to crack.
The benefit of a Brainwallet is, that you can not lose it as long as you use a passphrase that you can remember.