Following is a short guide on light armor sorcerer tanking as I play it - up to veteran dungeons and trials.

I play a Khajiit even though other races offer racial abilities better suited to tanking - I just love cats, that is why I chose Khajiit.

Depending on the race you choose (Altmer or Breton for instance) you might get more overall max magicka / health / stamina if you distribute your attribute points and armor enchantments differently than I did. But for a Khajiit tank, 49 points into health is good.

I put magicka enchantments on head, torso, shoulder and leg armor and stamina enchantments on feet, hands and waist armor as well as on my shield. On my weapon I put the hardening enchantment (grants damage shield for x seconds).

As for traits, I chose defending on my weapon, reinforced on my shield and infused on head, torso and leg armor. I am still experimenting with the four other armor pieces since I have not found reliable information on whether critical hits occur in PVE and how often. So at the moment I am using impenetrable trait on hands and waist and infused on shoulders and feet armor. Since I use 7 pieces of light armor which provide only about half as much armor as heavy armor the reinforced trait is not really that great because it only adds half as many points of armor as it would on heavy armor.

I use the 5 pieces Spectre's Eye set in combination with a 4 piece Vampire's Kiss set: 4 % more healing taken is always good for a tank and 20 % dodge chance for 3 seconds after using an ability that costs magicka is great since we will be using Lightning Form every 8 (or 9 seconds depending on its morph) anyway - so we might as well get the most out of it.

As for abilities, Bound Aegis (Bound Armor morph) is a must-have as it increases my armor to the same level heavy armor would provide - I put it in both weapon ability bars so I do not have to recast it when switching weapon bars.

A second must-have is Lightning Form which you may morph any way you like since both morphs are useful. Keep Lightning Form up at all times to mitigate incoming damage and generate threat on enemies close to you at the same time (currently I do 51 points of damage every second through it).

I wear 7 pieces of light armor for tanking so I picked every light armor passive.

Using only these two active abilites and the light armor passives and my tanking equipment I have a spell resistance of 2767 and 2824 armor points which greatly reduce the damage I receive.

The next must-have is a taunt: Either Puncture morphed to Ransack or Inner Fire morphed to Inner Beast. I picked both taunts since the first costs stamina and the other magicka, respectively, which grants me more freedom in resource management (stamina / magicka). Use your taunt on especially deadly enemies like (mini-)bosses to keep them from killing your team mates.

As for large groups of enemies I use Caltrops which for me currently does 53 points of damage to every enemy standing within the 12 meter radius 'carpet' for 30 seconds. You probably will not get the entire group of mobs inside the caltrops carpet but the majority of enemies should be targeting you instead of your team mates.

All other abilities I consider optional for tanking and subject to the situation at hand or personal taste. For instance as a distance closer you get to choose between shield charge, increased speed morph to Lightning Form or Bolt Escape and its morphs, whichever you prefer.