Objective Control
As a jungler, managing, protecting, and securing objectives is just as important as ganking and assisting your team in their laning phase. Crucial objectives consist of securing priority buffs and epic monsters, providing and matching jungle pressure, as well as looking to help a lane after a successful gank in pushing down that lane's tower for the first tower gold bonus. Understanding the order in which these objectives should be considered and dealt with will lead to more victorious matches.
Securing Neutrals
Neutral buffs, epic and regular, are priority targets throughout the entire game. Aside from counter jungling tactics, it is best to start either your red or blue buffs and move quickly to the other to gain the benefit from it, but to also deny the enemy from potentially stealing it. These buffs respawn every five minutes so it is important to always keep that in mind so that you're not all the way across the map when the buff is respawning. Post ten minutes, the Rift Herald will spawn and will last until twenty minutes. Alhough being relatively powerful, this buff is not more important to the overall game than it is to continuously support your lanes, so this should only be taken when there is nothing else to do on the map.
Applying Pressure
Applying jungle pressure can be very simple or can be a complete mind game. To properly apply pressure, you need to be making yourself known as a global presence. However, this does not mean you must secure kills with every gank. Getting the enemy to burn a summoner spell or to cause them to continuously fear a repeat gank is often a much better outcome than a single kill. On the other hand though, you must remember that the enemy jungler is trying to do this same thing as well. Planning their possible jungle route in your head, noticing where they were last seen on the map, and trying to respond with that with a counter gank of your own can dramatically affect the remainder of the game.
Towers
Towers are what stand before you and the enemy nexus. Therefore, it is easy to understand that in order to win, all towers must fall. However, you need to be smart in actually destroying them, especially early game. If you have a successful gank, say in the bottom lane, and you decide to push and try to take the tower, it will then be forever frozen in a worse spot for your bot lane. To avoid this, look to see if they're ahead enough to be able to roam elsewhere and make plays without the need for the farm that they will lose after taking that tower. Another note to bring up is that the first tower to be taken down will grant the team who destroyed it bonus gold. Despite it being a fairly small amount, it is often enough to push a person to their next key component for an item that will provide them with a huge power spike.