-Don't go over capped flag, cap it from the side that is closer to your escape route.Unless you are baiting or you are sure it is safe.
-Use fake tps to save your friends. For example: your ub has low health and runing away to base. He is on gold flag and oak is chasing. If he can make it without you getting there, sometimes it is just better to show tp to scare them off and then cancel it. keep your tp and your position in map.
-Play in an angle that you see the whole map.Zoom in and out.
-Bait, using consumables(sigil,pot..).
-check opponents levels and know their possible average DPS. Stay or run according to this information. Of course know yours and your teammates as well.
-Hp flag is usually more important on cataract, when it is a mirror match. Still the exp flag is the most beneficial.
-Use your consumables at the right time, you can aggro damage from your friends and bait more by doing last minute. but beware of stun and sudden death. Count enemy's CD's if you can. Focus on important ones like, grasp, pen, charm, pounce.
-as mentioned earlier in many guides try to use your interrupts wisely.
-Exchanging kills can be advantage as well. late game can be used to buy troops when leading on warscore. This can aslo be done depending on depending on DG setup.