Suitable Raku glazes mature at a temperature, which can be reached with a raku kiln. Generally just below 1000 °C. You can apply the glaze by immersing the ware in it, or pouring it over the ware or spatter it against the ware or in this case just with a paintbrush in three layers. Adding up to 5% Bentonite to your glaze makes it easier to apply with a brush. Spots without glaze will be black after the reduction.