How to do Discloure before new empoloyment

I have a few side-projects that I have been slowly working on when I can find time over the years. Many jobs require that they fully "own" you as long as you're employed by them, means whatever you do in the employment period is owned by the company.

How should I do a full disclosure before signing the offer letter? I want to keep what I had, further I also want to have the right to keep working on the side projects in the future and keep it to myself(out of work hours, and never use any employer's resource for that, and, never directly compete with the employer's market). The products are normally very different from what I will be doing once hired.