Using CBSubs you'd setup a PayPal gateway for PayPal payments. Follow the instructions in the CBSubs documentation as well as the instructions in the gateway it self carefully.
For checks you'd setup an Offline gateway, which will provide them a payment slip for them to mail their check. When the check arrives you can process their basket from backend to mark their basket paid.
No subscription becomes active until payment is received unless the subscription is free.
The below tutorial videos maybe able to also help get you started and become more familiar with the gateway configurations.
www.youtube.com/playlist?list=PLp0puRITgC7NcxbEMg7iTNboV_WhIsgaZ