C.M.
Here's my two cents: One - trust yourself - I often lack confidence and when I do, that's when my daughter (15 months) seems the most frustrated - if i can fake calm, make up a stupid game or tell her what she is feeling (ex - oh, you must be frustrated - yes, we cry when we are frustrated, hmm.. do you want milk? did you go potty? **** talking him through it)
Sign Language - YES! My husband is Deaf so with our daughter, we didn't have a choice but to use it to communicate with her so she could talk to daddy herself :) I have a teaching degree and am a certified interpreter - and it's been wonderful for her!
half the time i didn't think she was even paying attention, but at about 4 mos she was signing milk and knew what it mean, then next was i think dog, more, please, ... now she's 15 mos and doing, 'outside please', 'walk',' potty', 'garbage' 'banana' 'drink' and about 45+words. My frustration went down IMMEDIATELY and so did hers
She's now at the stage where she has to learn about her emotions - when screaming is appropriate, when crying is appropriate and what to do instead of those :)
Anyway, my sister's kids learned it til they could talk and then stopped using it except when we come over and they need to tell Uncle Tom something. They are all just fine too :)
Hope this helps! Having the kid watch videos won't help, you'll need to start using it yourself - go for the major sources of frustration for you and your son - you'll be great! And watch for 'approximations.' for noelle the sign 'more' was like her two fingers touching until she had better handshape control.