You have several options:
- Use the ready mobile themes that come with OMF and change the colours. For example, you can change the colours of the default blue theme to match the colours of your desktop website. This is done via the OMF Administration and it doesn't require any coding skills. You can see a demo of the OMF Administration here: http://omframework.com/demo/admin. On the "Advanced customization" tab, you'll be able to pick colours from your desktop theme or manually choose the colours that you like.
- Make small tweaks on the mobile website design. There are several articles here about this type of customizations: https://braiv.zendesk.com/hc/en-us/sections/200330426-Customization. We can also help with simple tasks such as changing the colours of certain elements, adding banners, links, custom text, moving items around the page, hiding certain items from the mobile site.
- Hire a professional web designer to make a custom design for you. If you think the mobile site needs a complete redesign, you can hire a professional web designer to do this for you.