How do I make a "drain board"?

To function effectively, drainboards need to be slightly slanted down towards the sink, so that water runs off and does not pool.

If I was to attempt this I would look for some tile with ridges for the water to have channels for the water to run into the sink, then use a border edging to make sure the water doesn't run off the edge of the counter. Waterproof the grout after installing. https://www.wayfair.com/MSI--Dymo-Wavy-12-x-24-Ceramic-Field-Tile-in-White-NDYMWAVWHI1224G-L2970-K~MVP4210.html?refid=GX107983240706-MVP4210&device=c&ptid=406337589308&network=g&targetid=pla-406337589308&channel=GooglePLA&ireid=58357990&fdid=1817&gclid=CjwKCAjwk93rBRBLEiwAcMapUavVa1BxzOxhc1OYBzUmypb0v6MWqBFtWgQZ2GY09nQMx_IRU-VYVRoC5SsQAvD_BwE

But really they have extra large drainboards in every color under the sun on Amazon https://www.amazon.com/s?k=drain+board&gclid=CjwKCAjwk93rBRBLEiwAcMapUTdpcDnOb2-0MSxIKObCtWyiqDACVXjpwLZ6ONAyPTdP_191uqIPIBoCkeoQAvD_BwE&hvadid=241951732769&hvdev=c&hvlocphy=9033057&hvnetw=g&hvpos=1o1&hvqmt=b&hvrand=3394661023751241539&hvtargid=aud-647846986281%3Akwd-343562225&hydadcr=24664_10400964&tag=googhydr-20&ref=pd_sl_5t3rmvu9wc_b

This is my fav.... https://www.amazon.com/Better-Houseware-Multi-Purpose-Cutting/dp/B002IB5LW6

You may like the look- but we had one. Takes up a LOT of space. As it is tilted, you cannot use this as counter space. It is just a place to put a dish drainer for when you hand wash dishes. I would not recommend one.