Sorry. Forgot to include that I used A LOT of picture cards that I got from a great website called Do2Learn which has a wealth of resources for working with special needs including picture card, songs, games, etc.
http://www.do2learn.com

My son tested at a 3 and 5 month old level in receptive and expressive communication skills when he was 2 years of age. What worked for me was play based therapy. My son and I would sit for 2-3 hours straight just playing, painting, drawing, play doh creating....playing with my child gave him constant engagement, promoted communication and speech, improved fine motor skills, improved eye contact and so on. Playing is fun but it is so much more. I can not stress how this method of connecting and teaching my son has changed our lives. He started speaking, he is able to concentrate on tasks for longer periods of time.

He was 5 when we started this- I homeschooled then and do now- he was in a private school one semester and they did not use visual cues with him like I asked so he did regress some then. He went from a blank stare to complying with requests fairly quickly. I have cue cards for showering taped beside the shower since he forgets steps there sometimes; we've used cue cards/visual cards for the toileting process, brushing teeth etc.
if he's receiving on a 12 month level, start there, without baby talk of course but easy concepts- a picture of cars on the box cars go in and model doing it as you say "cars away" or something like that based on your needs. Jaden is now capable of most self care, cleaning up his toys (admittedly not as nearly as i would prefer but he's 7 and a boy so.....), and completing basic chores like feeding the dogs, sweeping stairs, gathering laundry. It took me a lot of 1-1 with him but the payoff is worth it

Ah, yes phone is an awesome aid, Elizabeth! I keep pics favorited on my iPhone so I can get to them fast if I need to. It's been super helpful if he's upset somewhere and won't talk or we need to keep quieter (church)

Print pictures or use your phone or Ipad. If you are not 100% sure if he understands, use a picture or point to item. Slow down pace and wait for him to look at picture or follow your gesture. If his bear is under table, point to it (big gesture) and say Bear under table. Use less words and add when language improves. Use the "one up rule." Talk to him with one word more than he uses or seems to be able to follow. When it is time for bath, show a picture of tub and say "Bath time." "More than Hope for Young Children on the Autism Spectrum" explains it similar to this way. "An Early Start for your Child with Autism" is helpful. Maybe your library has one of them. Follow his interests. Label things that he is looking at . Label his juice when you give it to him, being sure that you have his attention. "Put on shoes." Hold his shoes and show him. you can eventually prompt less and see if he understands. The way you talk with him will work more than Speech therapy or diet. You are his real life and are with him more. Those things are still important. I would water down that juice.