Hi welcome,
The usual diablo stuff works here, for tanking go with as much Vitality as you possibly can get, then focus on damage reduction stats and blocking. The blocking part for your lets say shield tank usualy comes with dex investment, but as I mentioned earlier Vitality is your most important stat as a standard tank, try to get dex and str from gear or charms as much as possible. So standard diablo 2 stats strats work here.
Idk, Get as much as Vitality and def stats as possible, and as much damage as possible
Then according to your encounter, find, craft, create
appropriate gear. Keep an eye out for Absorbtion items they are great help,
Absorption% (Or Absorbs)
"Absorb% heals the player - which is equivalent to resistance. If you have 5% Absorb Fire, 5% of the Fire that would hurt heals you instead - roughly equivalent to 10% Resistance. It has a cap of 40%
Straight "Absorbs xx" is not active here so there is no way to heal from elemental damage."
Credits: Purerage
There is many different possibilities available in HU, for example a semi tanky Sorc life or mana shield, can do well vs bosses since there is no synergies, I wouldnt try it without a shield and descent dex tho, you basicly use your teleport skill to out play the bosses while nuking them and taking hits, that is if you are able to.
A lot of the time you will have to move a lot and dodge in hard fights.
I could go on and on about this, but Hero editor is your friend xD