Hi @andyprout82,
For syncing segments across Adobe Analytics and Marketo, the documentation that Pankaj provided above is great (for the native integration).
If you want to get data points (job title, person statuses, etc.) into Adobe from Marketo or send AA events (ungated downloads, product analytics events) into Marketo onto custom activities/objects, our company Datajoin offers a light-weight 'Micro Integration' to solve for this.
We just presented on this at Experience Maker's Live last week. Let me know if any questions and best of luck.
Thank you,
Sam