Bring the battery in and put a trickle charger on it.
Take the weight off the tyres so that you don't get flat spots on them and the bearings. Perhaps spin the wheels monthly.
Maybe run the engine up to warm every month or else just take out the spark plug and put a spoonful of oil in and then turn the engine over slowly on the kickstart to distribute it.
Drain fuel out of the tank and especially the carb as it can deteriorate and can in some circumstances block bits of the carb that are hard to subsequently clean. Can't think much bad can happen because of low temperatures.
I store my TTR for 10mths a year and have been storing it and other bikes for over 10yrs. The main problems are loss of battery charge, loss of tyre pressure, carb gumming up (even though it's drained) starter motor brushes sticking in their holders due to moisture and possibility of stuck exhaust valves.
There are many ideas on storage; from my experience the best way is to start and run the engine for 5min every 15 days and check the tyres. Been doing this for 5 years now and never had any problems.