leveling

As soon as you log in on seasonal/yearly reset or for the first time that season you want to choose your main character. Then sit through any new cutscenes if you like and play the first mission if it doesn’t throw you into it. It is very important for leveling purposes you DO NOT turn in completed bounties just yet. Play far enough into the story to get the seasonal artifact. Jump into a fireteam with at least 2 others and make sure your ghost has the Blinding Light mod slotted. Then you want to turn in all bounties on each character to maximize season level and artifact level/power. After your bounties are turned in progress through the story and work towards reaching the soft power cap of 1500 power. At this point normal gear drops will no longer benefit you and the only way to progress is through powerful and pinnacle rewards. continue through the story if not finished and turn in Prime Engrams as soon as possible. 

On your first character it is unlikely you will reach powerful cap on one character so be sure to run all powerful and pinnacle activities on that character. Once you have reached the max level on your first character switch to your secondary character and move the highest weapons over and spend time evening out your power increasing armor power. Once even you can progress through powerful or pinnacle activities. If you are getting close to the powerful cap of 1540 you may want to hold off on pinnacle rewards. Once everything is done on that character switch to your third and repeat. 

If you only have 1 or 2 characters focus on obtaining prime engrams as these will benefit you the most up until the powerful cap of 1540. when the second week rolls around you want to start on your third or highest character and again run everything you can. if you reached the powerful cap the only rewards that will grow your power are pinnacle rewards. these will get you to the pinnacle cap of 1550. once done on you highest character switch to your second highest and repeat. Then on to your final character and you should be just about there.