This is pretty much just a basic boss guide on what to pray/protect, the difficulty and what style I use vs each of them.
very easy = no damage taken at all, semi afk bosses with prayer
easy = some damage taken but not much attention needed
medium = semi decent gear recommended, lower kills per trip
hard = attention required, fewer kills per trip
Bandos (medium) - Pet? (yes) - I use melee.
Pray melee whilst killing the boss, pray switch the minions starting with the mager - use ecu key to save getting kc & minions are worth killing for drops.
Barrows (easy) Pet? (no) I use melee.
Pray melee vs torags, verac, dharoks, guthans, range vs karils, mage vs ahrim - requires spade, barrows items from chest are very common.
Chaos Elemental (easy) - Pet? (yes) - I use range.
Pray mage - located in 50 wild, can teleport out using max cape teleports - teleports you around and removes your weapon.
Demonic Gorillas (med) - Pet? (no) - I use range.
Pray mage - drops zenyte shard which are highly sought after - realistically they're easy/med but they can hit decently so you should pay attention.
Giant Mole (very easy) - Pet? (yes) - I use melee.
Pray melee - low hp dharoks is probably the best option vs these as you don't take damage - use rock cake (gen store) to get your hp down.
King Black Dragon (very easy) - Pet? (yes) - I use melee.
Pray melee & use antifires with anti dragon shield, make sure you're constantly antifired and you won't take damage.
Vet'ion (hard) - Pet? (yes) - I use range.
Pray mage - spawns 4 level 240 melee minions and regenerates health fully halfway through kill - currently isn't worth killing unless it gets nerfed
Venenatis (easy) - Pet? (yes) - I use range.
Pray mage - hits low amounts through mage prayer and also range (up to about 8 damage) - easy to camp
Zulrah (medium) - Pet? (yes) - I use range.
Pray range to begin with, change depending on the colour - green = range, blue = mage, orange = melee - wear ring of recoil/suffering to kill snakelings.
Will update overtime...