To begin, it is recommended to use Ranged and runescape 3 gold Melee in the event that your melee numbers are within the acceptable range (80+ Attack, 80and Strength). You could try magic - it could prove to be efficient, however it's generally costly (200GP per casting using the Polypore isn't cheap relative). Second, try using armour that is higher-defence until you're proficient with Prayer switching at TDS, then switch to Void.
how would you be good in prayer switching? if they are attacking with melee and then they make a roar, then you must decide between range and mage. If you can guess correctly then it's good but if it's not, then you're likely to suffer some damage before switching again... Correct me if i am mistaken... it's what i read on guides, but i've never been there, or completed the quest.
This is how I do it. It's a recurring pattern, so it's not like they switch their attacks randomly, don't they? No, it's not random. It's but they don't hit with melee anyhow and so it's best to hope for magic, or range. When they're about to begin moving, then when they start to roar, a small bone shard will pop up moving upwards although it's difficult to detect sometimes. Check for any signs that the demon's just been meleeing.
In slayer tower, you'd be able to kill them more quickly with melee so if you want go with the slayer tower option. Armor should be your best magic protection (Attack is melee, but its defense is based on magic, which is why d'hide and like) or should you want to pray (Bit of ineffective unless you're fighting the mutated creatures with cannon) then go for the best prayer security and pray for protection against melee. For weapons , choose your best slash weapon.
However I personally would do range, as they're quite impressive with range xp, which is essentially gigantic meatsacks. Additionally, there's a multitude of semi-safespots throughout the slayer towers that can be used to buy fire cape osrs separate them from.