The above optional tools are to help you do one of two things:
In my own practice, I use an eye mask frequently. One reason is because when I start thinking or worrying, I tend to open my eyes and get completely distracted. I'm more likely to stop my practice completely if this happens! I also use it when I'm in a bright room, or other people are around. Yes, I meditate in public. At airports especially (it keeps me in a great flow while I travel, and manifesting while traveling is way easier this way).
Earplugs help me out when there's lots of noise- whether traffic, tvs, or housemates.
Headphones are great when you're listening to a guided meditation or you're on the go and need some gentle music to create some white noise. Like in the airport, where you definitely won't be able to create quiet! Though the Chicago airport had a great yoga room last time I was there.
Extra pillows! These are for around your body to make you more comfortable. As a person with a long-term back and neck issue, I'm always aware of it and taking care of it. Sometimes, I need extra pillows under my legs in legs-crossed pose. Or, I need to sit up higher and stretch my legs out in a straddle. Or have one leg bent in and the other stretched out. Seriously, meditation is just about getting into a position that makes you comfortable and supports your spine, where you can sit up straight without strain. The goal is to become as unaware of your body as possible, and to become more aware of the "voice behind the voice" in your mind. That's what I call the Higher Self/Spirit/Intuition that you're connecting to in meditation. Because it's a quiet voice that's always there, always watching you and your other voice and simply observer. Through meditation, you'll start making connection with that voice, which many in the meditation world call "the observer." Over time you'll identify more and more with the observer rather than the louder, ego voice that is your typical thought-stream throughout any given day.
I know, I listed the timer as optional. But really, it's so very important. So make friends with the timer on your iPhone and find a gentle ringtone to bring you out of meditation without jarring your nervous system!
Finally, I love to have a blanket or a scarf handy. I like to drape it over my lap, or over my shoulders and head to make sure I stay warm. It's also a way of protecting your energy. In Chinese medicine, protecting the body from wind and chills is important to keep the body's Qi strong. Draping a blanket or scarf over the lap is something we always do in the form of qi gong I learned, because the lower half of the body is the most yin aspect. And yin must be conserved and protected. By covering it, you're engaging in energetic protection, especially as you meditate and reach into the deeper Qi of the body and communicate with the Essential Qi. We won't go there in this mini-course, but cool to know, right?!