Ideally you should roll the area after planting with a lawn roller. You can rent this device from many local equipment rental firms. The seed and soil need firm contact with very little soil or mulch coverage to germinate properly. Thereafter, reduce watering frequency enough to keep good moisture within one inch of the surface. Most experts say you still will need to water your Zoysia planting every other day for 5-8 weeks gradually reducing the frequency.
Water is a key factor in successful establishment of Zoysia.
If you can't water daily, don't plant Zoysia. Fertilize lightly at the end of six weeks. Remove all thatch and clippings and roughing the soil as much as possible to get better contact of the seed to the soil. Start in spring and seed heavily to get as much seed as possible worked into the existing lawn soil. Water frequently for at least 10-20 consecutive days during warm weather.