Get the bounties. Do daily mission. Do 2 strikes. Do patrol until you get bored. Hand in bounties. Takes about an hour and a half a day and after 2 weeks you have all the fear you will need from vanguard or drops. Alternately do it all in one day. About 4-5 hours but you'll be short on rep. At the end of the two weeks. This is assuming you have only just levelled to 20 this week and have basically no rep. It's about a 20 hour grind from never playing to lv 28 then the night fall and weekly heroic take over and your raiding. Strikes for marks. Patrol for rep. Bounties for experience. Heroic, night fall, raid, for gear above 31.