basically wait for your jungler and farm undertower. try to wait for her to use her W before you try to clear tentacles, but unless they're under your tower, don't bother, as it just gives her an opportunity to damage you. rush tier one boots, (maybe even tier two after phage) to help dodge tentacles, and if you decide to fight her solo , try and save your q for when she ults so that you can disengage and wait for her ult to end. I really recommend against trying to fight her solo, especially when you know her ult is up . This is because, regardless of how ahead you are of her, she can just shit out stupid amounts of damage. You won't out trade her lmao
Best of luck