Taming/Animal Lore/Vet/Magery/Eval Int/Necro/Spirit Speak
certainly not a PvP template (of course) but there are some things you can do to make it harder for the attackers. I am assuming that your seuit has 70 in all resists - if it doesn't make sure you get there because it will reduce incoming damage.
Fae Reim pointed you in the right direction:
you want to use a one-handed spell channeling mageweapon to get some defense against dexxers. Ideally you would have 120 magery and make up for the skill points lost through the mage weapon by extra magery skill on your jewellery. This would give you the defensive equivalent of 120 weapon skill. Make sure you fit 45 dci on your suit and weapon. Overcapping dci doesn't work anymore as far as I know. The mageweapon has to be a one-handed weapon so you can use potions.
Carry at the very least a couple of greater heals, greater cures and refresh potions. Ideally you would also carry greater strength potions and purple petals (always good to have extra hp), orange petals and enchanted apples. Make sure you make a macro for each of them so you can use them on the run. Invisibility potions as someone else suggested are not a great idea, especially on a magery character - they have a delay similar (if not equal) to the cast time of invisibility and if you take any kind of damage during this time it will fail to work leaving you exposed. So it'll alwas be better to just cast invisibility. Without stealth however, invisibility will only serve as a quick break from the attacker. There are multiple ways of revealing invised people and you can be sure your attacker has at the very least 2 or 3 available. You should mainly use invisibility to get spawn off you, give you time to mount and ethy/toggle flying or things like that.
Make sure you have at the very least the following magery spells bound to keys:
protection (this will reduce your faster casting to 0 and physical resist by 15 but it will let you cast uninterupted despite taking damage - very handy in some situations. Put 15 extra physical resist on your suit)
heal (ideally record a macro that casts the spell and then targets self - very hard to interupt when casting this with fc 2, only mortal and poison will be a problem)
greater heal
cure
greater cure (only way to cure lethal poison)
invisibility
teleport
wall fo stone (cast it behind you when running through a choke point to block people from following you)
I am assuming you play in wraith form. In that case you also want to bind this spell to a key as well so you can get out of wraith form quickly. If you're using a 5 slot pet make sure it is mountable unless you are a gargoyle. Make sure you have your pet near you at all times so you can get out of wraith form and hop on your pet as quickly as possible. Also record a macro for mounting your pet and bind it to a key so you won't have to click and loose valuable time.
Since you don't have resist you want to carry a trapped box at all times and make a macro to use it (breaks paralyze).
Having honor can be helpful - honor yourself so monsters will ignore you, then run in the middle of the thickest spawn and see if the attacker gets swarmed and has to retreat giving you a bit extra time to escape.
Let's now look at fc and fcr. Having fcr 6 is a must or else you can't cast spells back to back. There is some debate as to whether having 2/6 casting is better or whether 0/6 in protection is the way to go. Both obviously have their advantages and disadvantages. I would suggest having 2/6 casting on your suit so you can choose whether you want to cast faster (geat with mini heals for example) or turn on protection (thus reducing fc to 0) when necessary to cast slower but not having to worry about being interrupted.
When all this is done and you have memorized every single one of your macros it's time to think about the playing field - in this case the champ spawn area. Make sure you are familiar with the terrain. Find out what ledges you can teleport on so you can get away from attackers. Find out what the exits are - ideally you have at the very least 2 different escape routes in case one is blocked. Find out where the dungeon teleporters are, where to run as to not get stuck in a cul de sack etc. etc. Know where you have to run to so you can safely recall home (this is also something you should bind to a key to save time).
If you do spawns together with other players I highly suggest to use a voice chat of some sort and a map tool to make it easier for you to coordinate and warn others. Examples would be discord (voice chat) and UOCartographer (map tool for both, CC and EC users).
When under attack try to keep a cool head. I know this is easier said than done, especially for people who don't usually pvp (another reason why you should maybe try pvping - you don't have to get super good, but it helps not having to face two enemies at the same time, the attackers and the adrenaline rush. Get used to being under attack!)
Make sure you drink potions. Don't wait until you're at 50% health to use a heal potion, use it early and often. Use str potions and purple petals to increase your str and thus your hit points. Remove curses and debuffs by eating enchanted apples and heal yourself and others as much as possible. A nice advantage of having 2/6 casting with a mini heal macro set to automatically target yourself is that you can almost cast this on the run. It will cause you to lag a bit but you will be able to take a step or two away from your attacker in between casts.
Use wall of stone to block choke points (can't teleport over these). Paralyze fields on a choke point can also be nice to allow you to retreat.
The biggest problem usually is to momorize the keys so they become second nature and you can use them without looking at the keyboard. This takes practice... Hope this helps