Hey lytefunkieone

Yes you can highlight the piece i would recommend trying it out on another piece first i practice on old pieces now but at the start when i was practicing colouring i bought a stock system to try out different ways and find the best procedure for the best results. Be aware the hair on the piece will colour of bleach alot quicker then your own hair so your need to work out the best time for the desired results.

As for products alcohol free is best or as less as possible i am currently loving got2b Phenomenal Bodyfying Cream Gel. nice and light and good hold washes out easily with water.