Knock on doors.
Find a company that you want to work for and research them, so that when you find someone with the authority to hire you you will be able to tell them WHY you want to work for THEM.
Get a portfolio, print out pictures of your designs and put them in a nice folder, print them A3 or larger to show you have not just printed them from your dads printer but have made an effort to present them as you would present a proposal in the real commercial world.
Find the name of the person who has the power to hire you, or influence those that have the power to hire you, and make an effort to find them, and corner them in an elevator, doorstep, street, or wherever, for your "elevator pitch". Look up "elevator pitch".
Don't give up on the company of your choice. Go to the job page of their web site and apply for anything, cleaner, labourer, whatever.
Make friends at the company. Keep up your CAD modelling in GrabCAD.