I sometimes add extra sugar (the yogurts aren't sweetened) to give it more taste but that really depends on what soy yogurt you're using and how much fruit juice you add in.
These particular yogurts boost 4,6gr protein per 100gr, so by using two of them I get 9,2 grams of protein, some fat (5,4grams) and roughly 90 calories (46 kcal/100gr). Then I just add 100-200ml of juice to it to give it flavor and thin it out. I just shake everything in a bottle (you don't even need a blender for this!) take the top off and drink it. If you want to have more protein just toss in a third yogurt for a total of 13,8gr.
Since I'm trying to gain weight, I generally drink this along with some other snacks, but you can also enjoy this as a treat on it's own. Let me know how it turns out for you and if you have any variations that you like! ^^