Use the textured side for pasting with CrOx. Leave the smooth leather for normal stropping.

If you decide you want to try another kind of paste, I think you should get another maybe cheaper (as in less nice) paddle for that rather than treat the smooth side of the one you already have.

You need a plain leather surface for stropping, so unless you have another strop for that purpose you shouldn't paste both sides of the SRD paddle.

James.