I am a natural blonde, but I have been dying my hair for years. I wouldn't know my natural shade now even if it walked up and smacked me in the face.
I LOVE light blonde, the blonder the better in my book! After countless years of trial and error, too yellow, too orange, too dark, I have finally found the shade I love! All thanks to garnier olia hair dye. It's cheap, brilliant colouring and has a variety of shades and colours to choose from. I use 10.1 light ash blonde and sometimes 10.0 light blonde.
To achieve the best light pale blonde I have discovered is simple if you stick to these few rules;
1. Always always always buy a light shade that knocks out brassy yellow/orange tones, usually an ash blonde does this.
2. Buy a blue/purple shampoo to keep the blonde pale and interesting. But NEVER use it after first dying, the colour will seep into your hair and give it a purple/blue tinge (If this does happen baby shampoo works wonders after a fair few washes) unless this is the colour you want then avoid washing it in blue shampoo until you have washed your hair at least once and then every 3rd or 4th wash.
3. If going light for the first time you will need to start at a slightly darker shade and build your way up. Make sure you test your hair strand every time, not all makes and colours work on everyone's hair you will have to find one that suits you.
4. If you have brown hair then I would advise to ask a stylist first on how to proceed. Unless it says so on the box you usually have to wait until you are a lighter shade.
These are all the tips I can think of right now but if you have any or any questions just comment below!