Apply a pre-m to perevent weed seed germination (use tupersan or tenacity if you want to overseed). Apply an N fertilizer monthly (starter fert can be used) as during the first year, a new lawn needs plenty of food. Water regularly when there is no rain. Spot spray any existing weeds with WBG or if you overseeded use Tenacity untill the germiated grass has been mowed a couple of times. Winerize at the end of the year and then use standard schedules for fertilization starting next year.