First all of you need to learn his abilities.So watch the phinn's hero spotlight.Once you have figure out his abilities you need to practice combos with him like his Quibble followed by his Polite company and vice-versa.Now his ult forced accord pulls enemies closer to him.For starters there are plenty of combos that can be done with his ultimate.Like use ur ultimate followed by Quibble to stun them right after they are hooked followed by polite company to bring the fleeing enemies closer to your team .If you are new to phinn there are many wombo combos that you can try out with him like his ultimate followed by his polite company its still a good combo but less effective than ultimate+quibble+polite company.Now that the combos are done..Lets take up what to do and what not to do as a Captain Phinn.

Dont's
1)As phinn is one of slowest heroes in the game you have to be in good position almost all the time,because if u get caught out you will most likely be killed giving your opponents the upper hand in team fights.
2)You dont want to pull a fully spun up saw or any hero which will be benefited more from the pull than your team like alpha,saw,etc
3)Dont be out of position in team fights as phinn is one of d slowest heroes in the game if you are way behind your team in team fights your team is most likely going to lose the fight and probably the game.

Do's -
1)Use your Polite company B ability to buff your allies and bring enemy closer(remember that your B gives your allies bonus armour and shield depending upon the health,armour and shield phinn has.So its not that bad to build metal jacket or an aegis on phinn.
2)Buy tier2 boots or war treads early in the game on phinn as it helps him to keep up in team fights.

Play more with phinn amd practice his ult+A+B combos

Once you are confident enough with him you can create your combos with him and maybe even chain cc(crowd control) with him.
(WILL BE EXPLAINED IN ADVANCED)

If u play more and more with him you will notice that you can land blind hooks depending on the positoning of the enemy and chain cc,maybe near the gold miner's left/right top corner of gold miner or near the second treant of both jungle sides or if they are in jungle shop.Its a risky choice but if it pays off your team will surely win the team fight.Sometimes its good to hold onto to your ultimate and use it mid fight with a combo like cp alpha's ultimate into ur ultimate or baron's ultimate into phinn's hook.You will be come up with more and more new combos the more and more you play as captain phinn.

Secondly its not so bad to build an aegis or metal jacket on phinn beacause his Polite comapny gives your allies bonus armour and shield depening upon phinn's health,armour and shield.Its a really smart choice beacuse you can soak up alot of damage for your team and buff them up with your Polite company.

But if you are up against a high attack speed hero like ringo,saw,ect its better to get an atlas.You can use your atlas in multiple ways like by using it with your hookbut but it has a lower success rate as they will either block the hook or block stun (A ability) that will follow the Phinn's ultimate.If you are good phinn then you can use your atlas a second early before u hook/pull the enemy carry/jungler towards your team as the atlas animation takes like a second or two to activate.Secondly u can just war treads to enemy carry n atlas him.Lastly u can use it mid fight. :)

Remember that phinn's B reveals enemies too if they are in the range of the ability's radius like taka,flicker or kestrel.
You can use your pull defensively too like to pull away a taka or an alpha from your carries if they are low in health.

Now an important point chain cc(crowd control)- There are many ways to chain cc the enemy team or a particular enemy like-
1)Like phinn's ultimate into the Joule's A.
2)Phinn's hook into Celest's B ability.
3)Phinn's hook into samuel ultimate.
4)Phinn's hook into lance's A (Imaple)....The list goes on... For more info on chain cc check out its guide.


Lastlty remember thau you have to play more and improve.Yes the guides and tips help but you have to try it for yourselves to get better....Goodluck and now kick some butt on the halcyon fold :D