Leveling Up In Star Trek Online
Star Trek Online is one of the easiest games to level up once you know how to. As they add more content to the game, it really does make it really easy to level up. Once you level up one character, it gets easier.
As stated above, STO is one of the easiest games to level up in. The federation is easier to level up compared to the KDF side. The Federation has more content than the KDF side. The one thing that they both share is the featured episodes. Every time they put the featured episodes into a different sector space that the klingon otherwise would not be able to get into, they open up that sector space to them. Currently, you can get into all sector space but Sirius.
When it comes to leveling up, you have choices on what to do to level up; missions and pvp. With the future free to play release, you may be forced to play all missions.
There are a few different types of missions to do; star clusters, patrol, regular mission and featured episodes. There is also DSEs which are also called Deep Space Encounters.
Federation VS. KDF
The Federation has more content than the KDF.
Both factions, it is rather easy to get from Lieutenant to Lieutenant Commander. On the Federation side, you need to get to Lieutenant 6 in order to do the featured episodes. On the KDF side, you start out as that. Just doing the featured episodes, will easily get you to lieutenant commander. In addition do missions. So for the Federation side, you will have to do missions until you can do those featured episodes. Now those series do give out items and most of them don't level with you so periodically if you want the items for your level, you will though have to replay those missions again.
For the KDF side there is not many missions currently so the best way to probably level up is PVP and any missions that crop up periodically. With the KDF side, you usually end up turning in multiple objectives at the same time due to kills that you make. They have changed the level you can do the featured episodes at so it may not be possible to start doing all of the featured episodes at Lieutenant 10 anymore so that means using other means like doing star clusters, PVP, missions and so on to level up and get those particular missions.
If you can find skill points in the game, that is also a way to level up, but I suggest you do your missions first before activating it. I found by doing a whole bunch of missions and then turning them in you can easily go up a full extra grade.
You can find skill bonuses on the exchange. I don't suggest buying them off the cstore. I know it can be picked up in game, but I have only picked it up once so far.