MS Medium
 

I'm trying to prepare a medium. Wondering how much MS per litre should I be using? Also the % of agar? I've been searching and they keep using "a vial" or something of sort. I only have powder form

For germination I like half-strength MS, so half of whatever the sheet or bottle says (MS has a ton of different variations depending on what vitamins / sugars have been added in so each one will be different, but it should be labelled. I've had germination for multiple species on 1x too, but 0.5x makes media last longer and I've heard the 1x can be a bit stressful for some finnicky species' seeds.

Most of the time it's prepared in a flask or bottle, but really anything pourable and ideally with a small neck works. Made of material you can autoclave / pressure cook to sterilize (this is crucial).

I use 0.8%, sometimes 1% agar (w/v, so 8 grams in 1 liter for 0.8%) with good success. I like the softness of the 0.8%. A note, not all agars are created equally - you need a different amount of bacto agar (what I use) than Gelrite, etc, so YYMV depending on what you have.