If you are going to get new hair color or if you are getting new shade then the safest way is to pick what is best for your skin tone rather then what is in nowadays and what is hot and if you have shaded eyes then you can pick shade acceding to your eye-shade too so here are some simple tips for you.
First of all I want you to explain what is warm and cool tones, all those shade that seem cool and has a tint of ash called cool colors and any other called worm or bright colors.
Pale Skin, if you have paler skin tone like really fair, like twilight starts fair then you can pick all those shaded that look bright like, maroon, strawberry red, just stick with warm tones and they will marvelously effect your natural pale with natural shades, you can even try jet black too and if you have bright eyes then try red shades, and if you really can handle then Golden sun kissed blonds would look ideal over you.
If you have light skin and you have reddish touch in your skin too then all the shades of red is not for you at all, rather than that try some soft gold shade like copper, honey blond, golden, hazel gold and similar to that, will look best on you.
If you have natural or artificial tanned skin or a skin tone that has brown touch or warm golden then you are one of the most luckiest people cause you try any natural looking shade and it will go perfect with your skin tone, although any unusual shade like blue or mauve is not for you or sometime copper shades look a bit odd, although warm mahogany browns and reds are perfect for you.
If you have South Asian skin or Asian skin then the bright colors are for your, like maroon, cooper brown, and other warm reds, richer browns and if you are trying to look someone funky then try brown and blue shades they would look wonderful over you.