Ayeyayaya...
First tip: sing. Sing a lot. Sing all the time to songs by women in mid ranges. If you've gone through puberty, Karen O or Mariah Carey are out of the question but there are plenty of artists that sing in the Alto or High Tenor ranges that you'll be able to sing along with just fine. Before you sing, do those vowel warmups that FYFV has you do. They're really good for limbering up the vocal cords which can get pretty stiff without a good deal of usage. After the warmups, do some scales. If you don't know how, check YouTube.
Second tip: Record/Play Back. Every vocal coach worth their salt will tell you to listen to yourself. Screw the rest of the world for a while. You just do you. Both Andriod and iOS have recorder apps, some free, some not. Pick a tongue twister or a nursery rhyme or maybe an actor's warmup (I use Chippy Chopper, personally), and say it once. Listen to it and really hear the specific parts that aren't really 'good' to your ear and make sure that you pick them up next time. Wash, rinse, repeat. After a while, you may find that your exercise won't provide enough challenge. At this point, pick a book with a good story that you know the flow of and practice reading it into the recorder. Really try to capture the essence of the scene with your tone. Play it back, do the thing where you note the bad parts, etc.
Third: PRATT. I suppose that I might put together a tutorial at some point on this but PRATT (
http://www.fon.hum.uva.nl/praat/) is a super powerful vocal analyzer which can isolate frequency, formant, impulse, and a number of other vocal queues. If you know what you're doing with it, you can really dial in your voice. (Just checked at mine is actually at the upper end of the frequency spectrum and the middle range of female formant, so WOO!)
Fourth: Talk to yourself in the mirror. It's funny but a lot of people miss this one. Talking to yourself in the mirror will show you what the rest of the world sees when you're talking. I know some girls who have awesome voices but crap body language. 'S not so good. You really want to be able to express what you're feeling through your body language and this, as was mentioned before, will alter the pitch and tonal quality of your voice, and yes, smiling will reduce the tonal cavity in your mouth and so will reduce some resonance... but not like you'd think all the time.
Fifth: Give it time. I had a head start going into this and it still took a little while to get all the pieces of my voice really dialed in. Most people don't play with vocal sound effects or accents on a regular basis, nor do they do a lot of acting. If you did, awesome, you're probably 1/2 way there. If not, you've got some work to do and looking for a shortcut will give you shortcut-like results (half-baked, to say it nicely). Put in the time, put in the effort and you'll be rewarded by never getting sir'd on the phone again ('s been three or so years since I've heard that. pretty awesome, really.)
FYFV is a fine training program and covers all the bases quite well. A lot of the methods that are used to tune your voice are the same ones that are used in theatre so, Andrea actually has a good grasp of the topic through years and years of practice. If you follow it and, maybe play around with some of these tips, you'll actually go pretty far, pretty fast so, get to it and stop thinking about how to short-cut the process. One thing that no one tells you is that it never really ends. We're taking vocal ranges and really stressing them to the brink so it takes constant fiddling over the years to keep the things in check. :-P
P.S. - Water. Drink lots and lots of water. If you smoke, cut that out asap for optimal results. Tea and chamomile also help.
