195 days?? that's a while.

Depends on your kinks. Here are some thoughts:

• Card game: pick a random card each day. Each card means something. Like 2-10 is number of edges that day. Heart means edge to your favorite porn, club means edge to something else. The face cards mean something else -- no touch day, no underwear, anal day.. whatever you like.
• bondage punishment - if you touch on a no-touch or can't fulfill the requirements you get tied up for a while.
• butt plug punishment: you need to have one in all day. Punishing because it's uncomfortable, but also because it's distracting if you are denied.
• chastity belt -- if you have one or can get a cheap one. Have your friend hold the key for a set day/days. If you each have one you can hold each others keys and see who needs release first.
• erotic hypnosis -- not for everyone, but fun as a challenge. Pick a video or file for your partner to listen to a few times.
• exhibition challenge. Public adult only place -- like a bar maybe, see who is willing to do more. Loser buys drinks. If you want to live on the edge, amateur night at a strip club (I've never done that but know people who have).

oh, you can see I have a kinky mind.

Need to stop now :)