Samples to attach at delivery of work

[tomerrose]

Hi, does any of you have good tips regarding attaching a .jpg or other sample at every delivery, to join my portfolio? The site recommends it at every delivery, yet I’ve never done it so far, I don’t quite see what is meant by that, since the client’s work is always basically confidential.

Yet I’d like to add things to my portfolio of course.

So - does any of you (experienced) do this? If so, what do you put there?

I’d appreciate any tips,

thanks!