Hi alessandro...my apologies-- I read back through your thread just now and saw that I missed a question you asked me asking the name of the leave-in conditioner I use...... you can get it very cheap from the European hub of ` Hairdirect` ...it`s ``P.P.I. Enhance leave-in conditioner`` ...just click on the ` conditioner` link on the site and you`ll see it...it`s a green colour. I used to wear toppers and like you, I needed to shampoo my side / back hair frequently as it tended to be oily and as it was so thin it looked awful after sleeping on it but I didn`t remove the topper ..simply wet my side / back hair and applied shampoo to it and rinsed off as normal....you can wet your topper hair no problem ---it will inevitably get damp /wet in the shower in any event...just blot it dry with a clean towel ...the water won`t lift the colour and you can use your conditioner on the damp hair....I generally ` back` brush the hair so it`s standing up a bit from the base---that way you can get the conditioner into the hair rather than just on the ` surface`......style it, and apply a final dart or two onto the the styled hair...it will dry with a light `hold` which simply relaxes when you next brush it ..... hope you get your colour issue sorted out ...Hersute gives great tips and advice here and is always so helpful to everyone...kind regards.