I am not a fan of gluing anything to the actual speaker. Maybe you can rig something up to hold the cloth underneath the grill. On a $19 speaker I might not worry too much. That particular speaker won't have a lot of travel (low bass) so it should be ok. I would check how much that center cone moves and if it will hit the cloth while in use.

If you do want to go that way you could lightly stretch the material on a surface. Then get your adhesive on the speaker gasket then place it face down on the cloth. Once it is dry you can flip it and trim the cloth.

I have also seen some use good double sided tape (3m) which is a lot less messy. It holds cell phones together, why not your grill cloth?