Jakiro:
Liquid Fire is good when you want to push lanes quickly so as to end game before late game phase starts.
Ice Path - If you are the only stunner in your team, then this skill is your first priority
Dual Breadth- Level 1 slow should be taken before level 4 since it will come handy. For eg: If you are laning with a carry like Ursa/ Juggernaut/ Phantom Assassin/etc.... level 1 DB will help your carry A LOT
Macropyre- You may find it funny but I actually skip his ulti until I have maxed out IP and LF along with 1 point on DB. Simply because other skills are more useful in team fights. Macropyre is only good when you have a good lockdown skill like Faceless void Chronosphere or Magnus Reverse Polarity or Elder Titan Astral Stomp, etc/...
Items-
You can skip boot upgrade only if one of your other team member is making arcane boots. This way you can rush Meka.
Jakiro is slow, so I sometimes make Tranquil boots for speed if some other guy already have arcane boots. If not, then I\ll make arcane boots and later will buy Euls scepter.
Apart from those items, make Force staff, Euls, Veil of Discord, Pipe of Insight (only if enemy has good magic dmg AND no one else is making this). By the time you make all of these depending upon mat5ch requirement, match should be over
And if still the match is in progress and you have enough gold, then go for Shiva guard OR Scythe of Vyse OR Necronomicon etc... depending upon what your match requires.
But always remember
constant warding , dewarding and smoke ganks will help you win games in less than 35 mins.