The new jungle does make it hard to do a full clear w/o recalling, but one of the most common thing i do to make sure my sustain is on par is:
A: avoid birds. just skip them until after your first back.
B: SMITE RED. DON'T SMITE BLUE.
C: If blue first, smiteless blue, smite frog. If red first, smite golems, birds, then smite red.
Red smite = HP back upon smite which is more useful than the mana for the most part with blue smite.
Golem smite = 1 / 5 attk is stun = less damage done to you
Frog smite = poison damage AOE = faster clear = less damage done.
I've been doing a lot of WW and Pantheon jungle. WW i can stay in jungle till 6 and maybe use 1 HP pot by proper use of my abilities and smite.
Pantheon I can do a full clear excluding birds w/o backing, and thats only to buy items / heal up for an early dragon at that point.
Gone is the jungle where you can mash abilities and sit and AA. You need to use your abilities to interrupt the big monsters, stun them, and also properly use smite now.