I count everything. I find it is easy with a nutritional software, there are many to chose from. I set mine up with a "daily intake" that has everything I eat/drink every day, like my coffee, creamer, vitamins, etc. If for any reason I didn't have it, it is easy to go in and delete it.

I do estimate many foods, I don't weigh fruit, I use generic counts unless the fruit is larger than normal. I estimate very low calorie foods like lettuce, but always measure the other salad ingredients.

I have found that estimating too much leads to dishonesty in calorie counting, even though it isn't an exact count anyways and I soon stop losing.
You'll soon know which foods need attentive measuring and which can have an estimated calc. Everything gets a number though, even diet cola.

The only thing I don't count is water.

I am pretty good about counting everything, the things I think I usually skip out on would be my crystal light (5 calories) my gum and my vitamin that I take has 10 calories, its a chewable one lol

I count everything! No matter what!