Malphite Guide

Tips for Playing Against Malphite

-Free grasp farm! Q + Grasp trade as much as you can.
-Second wind, doran's shield, and your E passive will all heal most of the damage he does with Q, so he'll just be wasting mana.
-Be careful not to be low HP or too susceptible to ganks when he hits level 6, especially if you take ghost instead of flash like I do. (Flash might be nice for this matchup though if you're used to that!)
-If you can get a Q or auto on him before his passive shield comes back up, it'll reset the timer.
-His attack speed slow can mess up your ability to all-in him, so be careful not to take bad extended trades. (Keep in mind, you can mess his health bar up over time without taking much damage, so there are times an even trade isn't necessarily worth it.)

Swiftness Boots

Great boots in general, great boots for chasing Malphite, and the slow resist is nice against his Q.
Doran's Shield

I go D-Shield by default, perhaps you do too, but I think it's worth noting how useful it is in this matchup, given Malphite's main trading pattern is an occasional Q.
Hollow Radiance

I imagine Hollow is really good here, given you can just keep shoving Malph in, and he can't really beat you in a fight. You do sacrifice being able to kill squishies super easy with Heartsteel though, along with the range it gives. So, though this is good against Malphite in specific, I would still weigh your options.