There are two ways to do this, depending on how you want the member to be billed.
You can adjust the plan to be billed in a 12-month cycle.
You can add a monthly extra which will show up on their invoice every 12 months; otherwise, they are billed monthly.
Option 1 - Annual Membership
Go to Products » Membership Plans » Add Plan » Basic Settings.
Under the price, choose $X every 12 months.
3. If they purchase Time Passes, those will still come to them as a separate monthly invoice, or an immediate invoice, if you have activated the feature to charge your members for time passes immediately. You can find this under Customize » Features » Payments.
Option 2 - Additional Membership Fee Every 12 Months
This is useful if you would like the membership fee to appear as a separate line item, independent of the plan. For example, if the member is paying an annual membership fee of $150 in addition to their monthly membership fee.
Go to Products » Membership Plan » Add Plan.
Create the monthly plan as usual.
Under Extras, add the annual membership fee for $X / 12 months. They will pay it right away, up front (even if they cancel during the 12 months) and then Cobot will charge them again only after 12 months have passed.