Need help with siren

I am an UIM but I’m practicing on my main before I fight cuz UIM cuz regear sucks. I’m getting bankrupt on my main trying to kill siren. I’ve died over 20 times. I think I have mechanics down, I just can’t do enough damage. My main is 86 mage and UIM is 82 so I’m afraid it will be even worse on UIM. What am I doing wrong? This is the setup I’m using. Minus guthix rest. Most common deaths are running out of supplies or my health getting to low and dieing from normal attacks/ walking in melee distance when trying to kill pillars.

I am an UIM but I’m practicing on my main before I fight cuz UIM cuz regear sucks. I’m getting bankrupt on my main trying to kill siren. I’ve died over 20 times. I think I have mechanics down, I just can’t do enough damage. My main is 86 mage and UIM is 82 so I’m afraid it will be even worse on UIM. What am I doing wrong? This is the setup I’m using. Minus guthix rest. Most common deaths are running out of supplies or my health getting to low and dieing from normal attacks/ walking in melee distance when trying to kill pillars.