Provide a link where someone can download high res version.
Then an email where someone can send you the high res revised copy (via wetransfer.com).
If you mean the default Lulu logo placed there by the Cover Wizard, then it's only an option and you can click it to not be placed. An ISBN will not be placed if you do not use one, but a printer's barcode will be placed instead, but I think that if you use the Advanced Cover Wizard it will not auto-add either.
Myself and my friend combined know everything there is to know, but he's not here.