Putting your notice in professionally
Once you have accepted a new role and the important details are confirmed in writing, check your contract for the notice period and how notice must be given. Then speak to your manager and follow up in writing.
You can be appreciative and firm at the same time. Agree what needs handing over, keep your standards up and avoid turning the last few weeks into an argument.
A lot of industries are smaller than they look. Leaving well protects relationships you may value again later.