Well, it's not easy as he is a very picky eater and not fond of change! Breakfast is the easiest - gluten free cereal (from health food aisle at supermarket). Some of these are quite nice and he likes them. They are a bit pricey though, like all specialty foods. For snacks he can have rice crackers or corn chips instead of normal wheat crackers, biscuits etc. Again, this part is easy coz they are things he likes. Just look for ones without artificial additives if possible. I have started making GF bread as the loaves in the shops cost the earth. I found a good recipe on the internet which I am tweaking a bit. So with this I make him toast for lunch or afternoon tea. Also gluten-free pancakes are easy to make and can be had at any meal. I use a combination of GF plain flour and buckwheat, and replace the milk in the pancake recipe with vegetable puree (such as pumpkin or carrot or fruit) and a bit of rice milk. They come out fluffy and yummy. Apart from these things he has meat and fruit and potato. Veggies are a point of contention! Also I have partially replaced dairy with rice milk (look for the hi calcium variety) especially in cooking and in hot chocolate. When he wants some plain milk to drink he has A2 milk. Why? If you google A2 milk you'll find out why A2 is different to normal milk and a preferable choice for autistics.
It hasn't been as hard as I thought it would be replacing the gluten foods, just expensive! Dairy is harder to replace for us, that's why I'm compromising with A2, and he still has a bit of normal cheese.
ohh could i please get the recipe for you gf free bread?? my eldest is coeliac!! my bread never works lol!! also u can get gf pasta and snacks in most supermarkets.