Use this guide to help build your post-college budget. Resources are divided by category, roughly categoriezed with non-negotiable expenses at the top of the pages list, and negotiable expenses towards the bottom.
You can use the information in this source to research the average cost of gym memberships, and find pricing for membership to some popular chains.
Larger expenses, such as vacations, tickets to concerts/sporting events, are something that you should consider setting savings targets for. For more information, see the "Social Services & Financials" page.