I went red about three years ago, and I’ve never turned back.
I definitely recommend starting off with a demipermanant dye in a shade that appeals to you (remember that your natural hair colour will affect the resulting colour. The lighter your natural hair, the lighter the result. A platinum blonde will need a shade or two darker than a dishwater blonde. It will fade within a few weeks and wash out completely in about three months. At least this way you won’t be married to the result.
I am a natural golden blonde with strawberry lowlights, and my father’s mother was a redhead, so I had a feeling that red would work for me. I did a demipermanent in an orangey auburn, and loved it immensely. I look quite young in the face, and the more intense hair colour took away the immediate “Alice in Wonderland” face I presented. I still don’t look my age (28) but it’s a lot better than it was.
Since the demi-perm worked so well, I switched to henna, which is permanent and doesn’t even fade. I henna my hair once every three months or so, when I start to look blonde when I pull my hair into a ponytail.
I have no experience with permanent chemical dyes, but I found a site that has pretty legit-sounding advice.
Best of luck!