Memorize your lines accurately to alleviate the stress when you perform. Do not struggle to remember your next word, instead focus on your character and block everything else out.
Experiment with the techniques that work for you, for e.g. try reading it loud when you are practising your lines, record, listen and revisit the lines.
Practice is the only technique that makes room for improvement. We should practice for something greater than what we currently are.
Become a better version of yourself :-)
Hope this helps.