Ok to start off thanks giving time to read my build, this build works out for me very well an it does the same for you guys.

To start off ALWAYS go for middle, if someone tells you to go top or bottom, punch them in the face.
getting to level 6 and achieving your ultimate is the most important thing you need to do for early one man/bird ganking.

first to start off always harrass the other teams champion with your Flash frost, always try to get that double damage to the enemy and if possible hit them oly when theyre near minions, so that you can push and get those early hits on the turret.

once you reach level 2 or 3 harras the other defending champ as much as possible, but keep in note who isnt in thier lane. ALWAYS keep an eye out, good communication is the key. for a successful harass always hit the with your flash frost first causing double damage plus stun then you hit them with the frost bite dealing massive damage.

one you get level 6, its time for you to stack up on the Mejai's Soulstealer by going top or bottom lane, looking for low health enemies. If done correctly you should have 4-6 kills before level 11.

if you find yourself at early game the one getting harrassed, always turret hug, and stay near the turrets range. eniemeis tend to get greedy when you have low health, not knowing about your egg, so in other words. MAKE YOURSELF AS BAIT FOR THE TURRET FOR A KILL! :D. keep in mind always know the range of your turrets

if you find yourself running away and you still don't have the Crystallize, use your Q skill to stun them and run. or use flash in jungle edges or river edges to make your birdy escape

Pros:
If played correctly, chance of win
pusher
quick minion mob killer
wall will help team mates or prevent enemies from escaping
Ult slows down enemies for a short period

Cons:
TOO SQUISHY
Lacks defence