If you're soloing, you want to have good pip management so you can switch back and forth between hitting and healing. Use blades, traps and shields to defend yourself or set up a hit while also building pips for damage and/or heals.
Boost your healing abilities with your gear, especially the ring and athame. Carry low pip heals and, with that boost to your healing ability, you'll get more out of them. For example, a wizard around level 60 or so can easily get 800 health back from a 2-pip Fairy. Always heal yourself ASAP when your health dips below the half point.
Never enter a battle with less than full health. Port home to quickly heal if you must, then port back into your dungeon. It should hold your place while you fill up health and restore mana.
Life doesn't get a good "AoE" (attack on everyone) spell until level 58, so we are forced to take out enemies one at a time. To be most efficient, you'll want to hit once and be done. Boost your hits with multiple blades and traps, each one makes your damage spell stronger. You can use treasure cards and blades or traps from gear. They stack with each other to make your hit more potent. Use your Centaur spell on the weakest or most dangerous enemy. Once he's gone, take a moment to heal up, then set up another hit.
Get a pet that has damage, defensive or healing talents. A helpful pet takes the pressure off and can make a huge difference.
Use Team-Up to get some help on really hard dungeons or, if you have crowns, buying a henchman can be helpful. I use the level 40-70 Life or Fire henchmen most often, as they're cheap (50-100 crowns each) yet strong enough to get the job done just about anywhere. If you're up against a Life enemy that is spamming Death shields, a level 40 death henchman can remove them over and over, for just 40 crowns. You can earn 40 crowns just from doing Daily Assignments for a couple of weeks.
im a life wiz and i am having trouble with the dungeons any help would be great
You could use the team up feature. You can do this at the sigil and you might even find other people who are on the same quest who you could become questing buddies with
If you're looking for help with a particular dungeon and want to find someone on here to help you then you're more likely to find someone if you name the dungeon or group of dungeons (if there are a few together) so people know what they are getting into. There are lots of people who will happily help with a dungeon or a group of dungeons together but they might not offer if they think they might get into the awkward situation where someone really wants a questing partner.
I'm happy to help with a dungeon or two if you're stuck and can't find help via team up