The safest way to jump start any vehicle is to use an Engine grounding point for the negative jumper cable and connect it last. An even more safe way to jump a car is with a battery powered car jumper box as there is no pulse width fluctuation.
Also, if you rarely use the car (which I suspect may be the case here), I would highly recommend a device called a digital battery tender which is a small battery charger that plugs into the wall, you set the voltage setting, connect the eyelets or clamps to your battery posts and forget about it until time to go for a ride.
The all around safest way I have found to get a battery charged is with a Battery tender. A tender will charge a battery over an extended period of time (if the battery has been drained) and then monitor the battery and cycle to keep the battery at peak charge while not in use. I have several battery tenders and they work incredibly well for any application from a jet ski to Diesel truck.
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