This is something you can do with the help of a web design company as they will be able to help inform you on what works well for sites and what’s possible and smart. It’s one thing to come up with a great layout in theory, but if the colors have been shown to be off-putting for visitors and the layout takes too long to load over a mobile connection then you might want to rethink.
Still though, even if you use a website design company to come up with this idea of your site, you will still be involved in this part of the process and you will need to communicate your ideas to the company so they can be sure to create a site you are satisfied with and happy to represent you and your business.
A way to do this is with a pen and some paper which will allow you to draw up a quick sketch of what you think your site should look like and the rough positions of the various elements around the site. At the same time you also need to think of color schemes so try to come up with one or two different colors that you want to involve – a base color for the background maybe and one for text and images.