AACThaKid There is a
whole Tutorial in the opening post man!! On top of that there is a multitude of ways to get to the WiiFlow Wiki. Try wiiflow.info,
wiiflow.org, wiiflow.net or wiiflowiki.com. They all work I promise. If after reading and then attempting to get things going, try getting a bit more specific with your question and letting us know where your getting stuck at, or what's giving you problems, your question is so vague and shows such little effort into trying to get things setup it's almost appallingly rude.. Many of us here have spent a lot of time creating our setups, writing instructions, answering questions, and the OP and many, many users have gone as far as providing you with everything you need to get covers to show.
Do you even know if you want full 3D covers or if you just want flat 2D covers? The fact that you asked about covers in Wii64 makes me think you didn't read much at all.. there is a way to show 2D covers in the "GX" line of emulators, but not Wii64, but if you're looking for full 3D covers that's a whole different story.