I read an article in www.slate.com that said that the small things we do add up both because more and more people are doing it, but also because it influences our friends and families to emulate the behaviour. A survey showed that when someone stopped flying anywhere at all, their friends also started flying less.
Personally I used to get a new toothbrush each month. Now I have switched to bamboo. They last two months and arrive in paper containers, not plastic containers. The whole family have switched to bamboo now. That in it self does not have much impact, but:
How we use less plastic: We use bamboo toothbrushes, compostable bin bags, use bags made of textile for the shopping and reuse plastic bags if we get any. I have sewed textile bags for our veggies so when we bring veggies for work/school we use them instead of plastic bags. The textiles were leftover from some curtains I had to shorten. So that was a reuse as well. I have sewed covers for our bread moulds so we store the homebaked bread in the moulds instead of in plastic bags. We refuse straws when we eat out, will not buy balloons and only buy cotton buds with wood or paper sticks instead of plastic. Whenever we go to Lidl we buy plenty of oats, because they sell them in paper bags instead of plastic. I have knitted kitchen cloths out of an old knitted cotton blouse that had lost it's shape.
We recently went to buy cocoa. When we could only find cocoa in a plastic container, in individual plastic wrappers or in a container with cardboard on the outside and tinfoil on the inside, which cannot be recycled, we just decided we didn't need cocoa after all.
How we eat in a (a bit more) sustainable way: We have always been good at eating our leftovers. Now we also eat (more) homegrown food, have switched to eating more vegetables and less meat and have switched some of the meat from beef to chicken. We also sometimes eat pearl barley instead of rice. It is locally grown, cheaper than rice and has less carbs than rice.
Other sustainable habits: We use washing nuts, buy some second hand clothes and other second hand items, we donate to second hand shops, we mend and make do, we borrow items we don't use often instead of buying them and lend out our tools to others, We don't buy anything we don't need. The house is well insulated, we turn off the light in the rooms we are not in, we don't have the water running while we brush our teeth, we use rain water for watering our garden, we compost. We were in our thirties before we caved and bought a car. However, for short trips we will still walk on many occasions. (But it sure is nice not to have to walk for 20 minutes in cold, dark, wet weather)
We don't feel that we go without or that we have made sacrifices (except when it came to living without a car). We could probably do plenty more. My DH and I agree that we will introduce more and more sustainable habits each year.