I play the instrument (cunningly avoiding controversy)and I find breathing in and out trebles the volume but reduces the subtlety, so I use it to mark the rhythm. I taught my self to play and I pluck the tong, blade, vibrating thingy outwards from the cheek, this works fine apart from a tendency to lacerate the finger. I have some bamboo ones that I bought for £1 each from Oxfam shops. They use a cleaver reciprocating action so you don't actually pluck the tong but the end of the bamboo. Think they were made in the Philippines, and the great thing about them is you can tune them by adding a bit of bee's wax as a weight to the tong. The more wax the lower the pitch (about a tone before the sound suffers).I have a collection in useful keys from D up to A.
All the best Pied Piper