Challenging Smite is much better on Rammus than Chilling Smite because if you are getting invaded you have a much better chance of winning the exchange by smiting them when they are taunted so you taken less damage.

Alright so instead of taking refillable potion take 3 health potions. Why? because Rammus is only bad at jungler clear in the early game. Once he gets Cinderhulk/Enchantment it's much quicker to clear and take much less damage. So these 3 health pots are much more efficient at giving enough health to clear before going back and purchasing Cinderhulk.

Rammus is all about the sustained damage and long engagements. Cinderhulk ticks damage while the enemy is taunted and while the enemy is attacking Rammus his W deal 150% of the damage back to them, add Thornmail to that and he's an ADC's worst nightmare. But what about BOOTS? Ideally Boots of swiftness are the way to go but because Rammus is weak against AP mercury treads can be very viable. Ninja Tabi should be used when an auto attack based champion gets fed and can kill Rammus even with W up. *cough cough hyper fed Yi cough cough*

Abyssal Mask is great on Rammus against some AP. Rammus' main damage is AP so Abyssal Mask increases the amount of damage he does while he survives more Magical Attacks. Deadman's plate is very solid on Rammus. With Armor to survive and scale with his passive to the health to help with his low HP for a tank (but is balanced out with the amount of armor) to the passive of the item when Rammus speeds around at the speed of sound so he can clap someone with that extra magic damage

Ideally without any insane threats on the other team, Rammus wants to end with Righteous Glory and Randuin's Omen. This completes his fully combo that can win games. Step 1: Engage with Q and Righteous Glory Step2 : once your in Randuin's Omen to slow them and prevent them from escaping Step 3: have the team clean up the mess of an enemy team you just created Step 4: Profit. But what if there is a big threat on the enemy team that you can't handle with the normal set up? Gargoyle is great if your team just needs even more of a tank in team fights. Soak up damage and cool downs at the cost of damage is enough for your team to clean up. Frozen Heart for an extremely AD heavy team (4 or 5) and Adaptive Helm for champs like Teemo. Also Wit's End is here because I thought it was pretty cool because even more magic damage on basic attacks, MR and attack speed to stack with E and Precision Runes.

Remember to use potions. These can turn the tide of a team fight or even a game is used correctly. They last for 5 mins or until you die. All three potions can be Used at Rammus but only one can be activated at a time. And don't worry if you have a full inventory buying one just drinks it instantly. Elixir of Iron is great for the Tenacity it gives so if the enemy team has a lot of CC down this boy and get out of CC much quicker. Remember Rammus does AP so Elixir of Sorcery can boost his damage a good amount. Lastly Elixir of Wrath can be fairly useful because Rammus has decent attack speed when taunting and it can be used to get that bit of extra health that might be more useful than Elixir of Iron

Rammus needs red to keep up his health, Krugs can offer a bit of resistance. As in you kill them so slowly you're going to take a good chunk of damage. But for full clear you want to take red buff, Krugs go for Scuttle because it should come up towards the end of the fight with Krugs, clear raptors easy then get Wolves, Blue and Gromp. At this point if you have enough health try a gank top, make sure your laner knows because you rely on others to finish off the people you are taunting. If you don't have enough health for that back and buy. Rinse and repeat, become a tank and engage for you team for those favorable team fights.

Rammus' Basic combo is Q engage then E taunt and W to deal the damage. Ult is on a pretty low cool down and between ganks farming you can have it up almost every time you engage. Also Ult does double damage to Towers so you can help take off a few nocks of turret plating early game with a good push.

Aftershock should be obvious, Taunt with that and it's a combo made in heaven. Demolish with your ult makes you a solid threat against turrets, you can take font of life if you want to to be extra supportive but I find demolish to be more useful pushing objectives. Bone armor is good for quick trades but I recommend Conditioning to be a real late game menace. Unflinching is good but Overgrowth helps with the small amount of health Rammus has (for a tank) Also if there is a lot of AP feel free to change one maybe two of the +5 Armors to +6 MR