The three basic types of meditation are metta meditation, mindfulness meditation and focusing meditation.
Metta basically means loving kindness. The idea is that you start with yourself, try to gather loving feelings towards yourself in the sense of "May I be free of hate and experience kindness" or something like this, then direct this lovingkindness towards someone close to you, then someone not so close and then finally to someone you hate. The idea is that if the plan works out, you'll be able to experience lovingkindness for your enemy or at least wish that htey are free of hate. If you think this is cucked, then you don't know how terrible hate can be and how it can tear you apart inside and make you unable to focus on anything because you have these outbusts of total hatred that makes you feel like your blood is literally boiling.
Focusing meditation is focusing on a mantra, for instance
What I do and recommend (and what you will find most of the time if you go to a meditation place in the West and which is also done by various Buddhist circles, in Tibet, in Zen meditation) is mindfulness meditation. Basically, you are mindful about what's happening within you. So you sit down on a chair with your butt a bit above your knees (just use some extra pillows), then breathe through your nose and focus on your breath. Whenever your mind begins to wander, you try to realize what is going, become aware of these thoughts consciously and then gently return to focus on your breath. You can also count your breathe, count 1 for in and 2 for breathing out.
The idea is to prevent your mind from wandering without you being aware of it. The idea is that you become aware how thoughts, feelings sensations arise .. and pass ... and arise ... and pass. And everything that arises will pass and everything that exists will go extinct eventually.
This is easier said than done. I recommend doing it regularly but not too long. Instead of making it something "special" you do once a week but then dedicate a whole day to, make 15 - 20 minutes each day. Just focus on your breath. Soon, you will fail. Try to be aware of how you fail. Try to be consciously aware of the mind, feeling, sensation that causes you to fail. Explore this feeling. How does the hatred feel? Does it have a color? Is it red? Warm? Hot? Is it in your throat? Or your forehead? Just be consciously aware of it. Eventually, gently return to your breathing.
The goal is that you do not identify with these feelings and sensations anymore. You are not supposed to be "attached". Not attached to feelings, things, nothing. These feelings are not "you", they are not "I" ... they are just something that arises and that passes.
If you want some books/youtube with people who are good with explaining this try Sam Harris ("Waking Up"), Joseph Goldstein ("Mindfulness)" and Robert Wright ("Why Buddhism is true")