Hey Erydiel! I've never personally been contacted by deities or spirit guides during meditation, so you're not alone there. It might be possible with some types of guided meditation, active imagination, or trance state, but that's not been my experience with meditation.
For me, meditation is just about being very present in the moment, paying attention to my body, and quieting my inner monologue. Which makes it sound passive, but it really requires a lot of concentration. It's a kind of focused awareness, where you are just paying attention to your consciousness.
Different people have different ways to achieve this, such as paying attention to the breath, as Holda mentioned, repeating a certain word ("Om", "One", etc.). You might have to experiment with the meditation that "works" for you. I have a hard time with ones just about breathing, but since my mind is a constant inner monologue, the first one that clicked for me was this meditation poem
, where I could focus on words like "deep" and "slow". (in contrast, my boyfriend likes to concentrate on the temperature of the skin on his hands when he meditates -- so there are a LOT of different techniques you can use!). I've recently started taking Tai Chi as a form of moving meditation, which has also been quite helpful.
Meditation is often recommended prior to enacting a spell or ritual, because it helps separate one mentally from everyday life and prepare for magical or ritual work. I often meditate briefly before divination.
Like Holda said, it takes practice. I'm told it's like any other form of exercise; meditation gets easier as you exercise your mind in this way. Of course, when you meditate, it's quite natural for other thoughts to drift into your mind. When that happens, just acknowledge it (don't judge yourself and beat yourself up for sucking at meditation!), let it pass, and gently bring your attention back to the center (whether that's your breath, a mantra, or your motions).
Hope that helps!