योगश्चित्तवृत्तिनिरोधः ॥

Seeing; just seeing, the what is, not the what if, is MEDITATION.

To enable and let you BE, is the purpose of Meditation.

While you look at everything that is happening outside & is able to remain quiet inside because you have realised that every modification in your mind only projects something that was already present within you. That no one is responsible for what happens within you. However, you are responsible for how you respond to what happens within you. This profound realisation enables you to look at everything & everyone as an extension of yourself. Not figuratively, LITERALLY. You are in MEDITATION. You are in YOGA (union).

Unintentional Meditation – simply observing thoughts, emotions, feelings & sensations. This is the ideal way of learning to meditate.

Intentional Meditation – either anchored to a Mantra or a subject you want to find clarity on.

If you learn the art of seeing without judging, speculating, calculating or evaluating, you are meditating. Being quiet is meditation.

Benefits of Meditation!
Regulated nervous system.
Better digestion & overall health.
Better sex life. Better mood.
Better memory & intuition.
A fresh outlook & openness towards life.
Lowers resting HR & resting BP.
Increased focus & productivity.
Increased self awareness & reduced mental chatter.
Stress is now your ally.
More restful SLEEP. Reduced sleeping hours; more time in hand.

-Before Sunrise. Post-Sundown.
-First thing when you wake up.
-30 min before or 2 hrs post lunch/dinner.
-Anytime of your preference but empty stomach or right before meals.

-Before Sunrise. Post-Sundown.
-First thing when you wake up.
-Absolutely any time of the day if you have some practice.

However, most individuals need some kind of stillness in the body to finally be able to still the mind. They should first practice Yoga Asanas. Or any other form of physical
exercise. Yoga Asana is the best way to still the body. Then stilling the breath and then meditation.

Deep breathing. A mindful focus on natural breath. Body Scanning & letting go. Yoga Nidra.
Practising Meditation before sleeping will tamper with your sleep, as during meditation the body is already in deep rest. This shouldn’t be a challenge if you have been
meditating for years.

If you are new then 15-45 min, as per your ability. If you are meditating for quite some time then as long as you want to sit. Listen to your body.

Focusing on something is concentration. Focusing on the breath is Mindfulness. Body & 5 senses scanning is Mindfulness.
Meditation is when you sit with closed eyes and simply make yourself available to every thought, emotion, feeling and sensation. Gradually thoughtlessness is experienced for brief durations. With prolonged practice you start to enjoy sitting, walking and doing the basic things of daily life with joy.

Mindfulness leads to better Meditation. Meditation aids better Mindfulness.

By being trustworthy. 
Simple as it sounds. If you trust yourself and can rely on yourself, then trust will never be an issue for you. Whoever does what, when you are free in your mind and heart, nothing will affect you. Having said that, there will be exceptions, but even then, this self-reliance will ensure you are ok with everything in the end. And of course, daily meditation to build that internal resilience and to respond consciously.