A Logo guide isn’t the only thing to consider when designing a brand identity. It’s a good starting point however and is definitely needed before you can begin designing a website or creating brand assets & marketing materials.
Other things to acknowledge while branding yourself are your mission, values, position, purpose, brand voice, tone, & feel.
Plan your brand guidelines, and remain consistent with them. In turn, your branding will be more memorable and trustworthy in the eyes of your target audience.