Here is what i can suggest you. This is the fastest way in my opinion. But be aware that destiny can be a long and tedious game. Be patient. Play a lot of strike, you will eventually get all blue armor with a max 15 light for all the 4 kind of armor, if you upgrade it you will reach lv 25 easy. In the process you might have lucky legendary drops. You want to be able to to do the strike lvl 24. Pvp is not effective to get gear. You can be lucky but it is very unlikly. Strike lvl 24 is the best to have a bunch of of blue engram. Do has many pve bounties as possible to get your rank 3 vanguard. Youll have the chance to buy legendary gear.youre limited to 100 marks per week if youre very unlucky and never get a lengendary engram it will take you 3 weeks to get all youre armor legendary. Once you have all your legendary armor upgrade it until you get at least lvl 27, and then the fun begin. You get a team of six people on destinylfg.com and you do the raid on normal. You hope to get the raid armor bcause its the only way to get 30. You need shards to lvl up your armor so do the daily mission and a public event every day. Here is my tip for public events: in the cosmodrome: skywatch every xx:00 and xx:30 +/- 3 minutes. The divide: xx:15 and xx:45 +/- 3 minutes. When you spawn in the steppes go left for skywatch and right for the divide. If you even want to go faster, I HIGHLY recommend you to start 2 more caracter of the same class and do everything i said on all three. That way you will get 2 more chance at the raid every week. Thats how almost everyone do it. Good luck gardian.

Buy from Xur and then you're done.