I find it's better to look at each ingredient rather than the smoothie as a whole.
For example, 1T chia seeds is a little less than 1 serving of fat. 1 cup mixed berries is 1 serving of carbs, 1 1/2 cups bananas is 1-3 servings of carbs depending on if it was sliced banana, mashed banana, etc.
The 6 leaves probably don't even equal one serving of carbs... I would treat it as a 1/2 serving. The almond milk is 1 serving of protein & I have no idea what the nutrition analysis is for wheat grass powder to make a guess (I'd need to see the label).
REMEMBER TOO that No one food is going to be all carbs or all protein -- so even though almond milk has fat it's MOSTLY protein, which is why it's treated as such. Even brown rice has protein in it, it's still MOSTLY carbs, and so on.
Look at the definition for each serving and compare that to the nutritional info of the food you want to eat in order to decide if its a carb, protein or fat and how much of it is 1 serving :-)
A serving of protein is roughly 100-130 calories with 18-25g carbs and 5-10g protein and 1-4g fat.
A serving of grains and fruit carbs is 100-150 calories with 20-30g carbs, 1-4g protein and 0-2g fat.
For vegetable carbs, it's based on selecting three items for variety (who wants to eat three cucumbers to get a serving?). Each partial serving is 30-40 calories, 7-8g carbs, 0-2g protein and 0-1g fat so when you add three together it mimics 90-100 calories, 20-30g carbs, 3-6g protein and 0-3g fat
A serving of fats is 85-100 calories with 2-6g carbs, 3-5g protein and 8-10g fat.
But really, the easiest way -- is based on 100 calories -- if you eat 300 calories worth of spinach you know it's 3 servings. EASY!