Double process blond is good. The best blond hair colors are multi tonal and colored twice.  A root lift a few levels brings a softer color to slick on on the strawberry and vanilla blonds.  Just a few sprinkled platinum thin streaks is great too.  After the natural color is lifted you need to do  three color foils.

For you the hair curious:  A combination of two lighters each with one stronger and one lighter developer and one blond tint with 30 volume developer

Remember to put the gloss drops in your hair before and a little after you blow-dry to get the healthy shiny big curls.