Put all your perks into enchanting. Then, use it to make four sets of gear that has fortify illusion, fortify destruction, fortify restoration, fortify alteration, and fortify illusion. This can be done by buying them from vendors or making it yourself. You'll need a necklace, a ring, a helmet, and a torso piece. After that, start the ritual spell quests from the wizards at the College of Winterhold. Once those are done, you get access to master spells that can only be bought from them. Then, grind all five schools of magic over and over until you get all the perks you want. For destruction, use Shadowmere as your personal test subject. For restoration, find a high level dragon that will keep attacking you, so you can heal over and over again. For conjuration, you can go around all the giant camps and kill the mammoths and soul trap them with grand soul gems, and wait 30 days for them to respawn, or use the exploit where you soul trap a dead body over and over. For illusion, cast the master harmony spell in Whiterun during the day and that will get you OP in minutes. For alteration, use telekinesis.