I've done it before. It's a bit tricky because you have to push harder than you think, but still not too hard. Within a few, I got good enough that the snake barely noticed. Make sure you're doing it in the right direction so if they wiggle, they wiggle towards the syringe instead of wiggling it out. Also, if you want to gain confidence, you can practice on a raw chicken breast - sounds silly, but it's recommended because the texture helps people understand.