SKILL-BUILD:
Level 1:
Level 2: 
Level 3: Level 4: Level 5: Level 6: 
Level 7: Level 8: Level 9: Level 10: 
Level 11: Level 12: Level 13: Level 14: Level 15: 
Level 16: Level 17 - 25: JUSTIFICATION:
Rocket Flare at Level 1 will give you a great advantage in last hitting creeps and also serves as your tool to cancel healing of enemies[salve / clarity].
Maxing Battery Assault as soon as possible: You will need this skill to harass your enemy by going near him and then relentlessly attack him to death. Note: Keep in mind that you should cancel the 'backswing animation' of clockwerk's attack and simultaneously walk towards the target to achieve the full potential of harassing with battery assault.
ITEM-BUILD:
STARTING:
x2JUSTIFICATION:
4 pieces of Ironwood branch gives you more HP, more MP, and +4 attack damage which is what you need to have that laning advantage. 2 pieces of Healing Salve will make you last longer in the lane.
Also, the Ring of Protection is there so that after you farm up 325 gold. You will buy a SOBI MASK and make it a Ring of Basillius.
Ring of Basillius gives you that extra edge in harassing your enemy. Increased mana regen is good, the armor bonus is great because you will be able to tank extra hits.
CORE:
EXTENSION:
into -> 
if ableLUXURY:
into 
JUSTIFICATION [CORE , EXTENSION and LUXURY]:
Aghanim's Scepter gives you the ability to perform ganks more often because of the reduced cooldown of your ultimate.
Urn of Shadows ensures you that after every successful gank, you gain a free healing salve. Not to mention the increased mana regen is great for clockwerk.
Hood/Pipe grants you and your teammates extra survivability in team clashes against spells which is always great however you look at it.
Radiance is pretty good considering you are always at the center of the fight and you tend to follow enemies a lot.
While Vladimirs is just an optional item considering your core is an RoB. It is still a great addition to your team if no one else would want to buy it.
OVERALL BONUS [LEVEL 25] (STAT GAIN/LV. and ATTRIBUTE BONUS EXCLUDED):
+60 MS
+25% IAS
+1.4 Armor
+656 Hit points
+150 Mana points
+12.72 HP regen/sec
+0.4 MP regen/sec
+50% MP regen
+30% Magic Resistance
+84 Attack damage
+16% Lifesteal (Aura)
+15% Attack Damage (Aura)
+5 Armor (Aura)
+0.80 MP regen/sec (Aura)
Attribute Switch [Treads] - useful for gaining a little bit of mana when needed.
Soul Release [Urn] - very useful for healing yourself after ganking.
Burn Damage [Radiance] - 40 magical damage/sec combined with battery assault HURTS a lot.
Upgraded Ultimate [Aghanim's Scepter] - reduces your ultimates cooldown by a great amount.
Barrier [Pipe] - your team gains extended hit points in a clash. ^_^
GAMEPLAY
At the laning phase, make sure you use rocket flares to both last hit and harass. You can also use it on the sidelanes too so that the enemies will always have lowered hitpoints which is beneficial to your allies.
As much as possible, try to isolate the enemy hero in your lane using battery assault.
Preferably engage the enemy exactly as soon as his creeps are all dead or at least only 1 of them are alive. Then go for the kill. Don't worry too much about the tower because RoB grants you additional armor plus you have Salve's.
You should be able to kill your opponent 3 to 5 times at the laning phase if it goes well. Luckily, if your opponent is not that skilled enough to face you; you will be getting roughly around 10 to 15 kills just in the laning phase [My record is 14 kills. [14 minutes game time, kills of only 1 hero, my lane opponent]
After the laning phase, you should now have farmed an URN and a POWER TREADS. Now, you are to perform as much ganks as possible before the game hits the LATE-GAME PHASE because by then... you won't be able to gank enemies that easily.
Use your COG to isolate Agility heroes or Supports [in short, isolate the ones that can be killed within the duration of the cog] and then chase any retreating enemy hero with your battery assault or hookshot if you still haven't used it yet.
You should now have farmed your core items and luckily, a pipe and radiance.
That's pretty much it.
at Late Game, it all depends on how you initiate the clash with your HOOKSHOT + COG + BATTERY ASSAULT + [PIPE (BARRIER)] if you will win or not.
That is all.
P.S.
I mostly pick clockwerk in drafts when the enemy picks Nevermore, Tinker or any hero without disable as a mid-laner because they are pretty much 100% KILLABLE when you reach level 3 and have an RoB and Boots of Speed[if the enemy also has boots of speed, you really need this too][provided they don't have their supports backing them up]. /gg
Especially if the enemy also picks Earthshaker. Clockwerk's skills will make sure Raigor cannot cast Fissure and Enchant Totem.
