Using this recipe, I followed it with supplemental instructions from this YouTube video. To make vanilla macarons, I added 1 teaspoon of vanilla extract to the filling as it was being mixed. And to spread the filling, I used a knife, which is why it doesn't look as professional as it could have, though I like how they look. (Ignore the red glare on the macarons in the pictures, it's a result of the plate they're on.)
I had a lot of filling left over, partly because my sister got half of the macarons for helping me, and she liked them better without the filling, so she chose to just eat the cookie shell part. But even if I had filled those macarons, I think I still would have had filling left over.
Not everything in the instructions was entirely clear, but with the combination of the two sets of directions, I made it work and have been loving the macarons! I'm definitely making these again.