What common sayings will I want to know in Sign Language?

I am teaching myself some Sign Language. What sayings are important to know? What sayings/phrases do we use a lot in english?

So far I have:

-Happy Birthday
-Goodbye
-I love you
-See you later
-How are you
-I am good

And a few others regarding school.

Give as many as possible please!

THANKS!
.