in early game, get every exp you can, take every last hit you can,DONT DIE BEFORE USING FIRST MIDAS you can stay back in area of exp. also you can use meteor for sweeping creep waves. it will not be a waste. also always check other lanes for sunstrike killsteals/killsecures.
**use your midas only on big neutrals creep[/b]**
if they have silence, rush euls,
if they have dodgeable stuns or slows rush blink or force
if your team do not have some setups for your skills, again you must rush euls
then you will go straight for aghanim's.
octarine core is a big plus. you can use all your skills every 40 seconds, it will make every teamfight and every highground defending actions better.
you may need a bkb, if you think so, rush bkb before octarine core.
hope this build helps.
good luck, have fun.