Find the most conducive spot at home for meditating in, set it up, and stick with it. Overtime you'll gradually settle into that space, and before long you'll find yourself looking forward to returning to "your spot".
It takes time to figure out a posture that works for you, so don't fret if you feel fidgety or keep falling asleep at the start. Keep your posture as upright and wakeful as you can without straining the body. Don't worry about twisting your legs into a full or half lotus - your posture just needs to be stable.
Consistency is more important than duration for a start. Aim to establish a daily routine. We're trying to get the mind and body used to resting in stillness, and practicing once in a while isn't going to change that. Begin with a shorter duration, say 10 min a day, and gradually build it up to 15, 20, 30 min.
By the way, you may not need special meditation cushions. I gather whatever cushions I have at home and arrange them in a way that works for my body.
If you already have a regular practice, what has worked for you? Share your wisdom!