MOISAIC -What is the best adhesive/grout to withstand British winters?

Use thinset mortar instead of adhesives for outdoor mosaics. If you want to use and adhesive, use something solvent-based like Liquid Nails brand construction adhesive, but be aware that there are fumes, and the larger size comes in a tub which requires a caulk gun. Most people find it is easier to mix up small batches of thinset than it is to use a solvent-based adhesive. I can't wait to see how yours comes out!

You might consider molds for making cement stones for stepping on. Step: 1 Cut a peice of clear contact paper to fit in the bottom of your mold with the backing removed and the sticky side up. Step 2: Place your odd and ends in the mold with no sharp points down. Leave a small gap all around (between) your odd and ends. Step: 3 Mix and pour cement (from your local hardware store) into your mold and level it off, make sure no bubbles in your poured cement. You can use a butter knife stabbing straight in the cement and move the knife out slowly so not to change or mess up the cement. You just want to remove bubbles or some small gaps that might have formed. Let dry COMPLETELY!!! Step: 4 After your stone step is dry remove it from the mold turning it rightside up. Remove the contact paper and then you can place it in its new home. Make as many as you want.

Note: the contact paper is used to keep your odd and ends in place but you could use it to make a pattern in your stone step. Happy Stepping!!!