This is a commonly asked question, and one that can vary depending on your particular project. Here are some tips, though. If folks have some good suggestions in addition to this, please add them to the string.
1. Lay out your design. Being prepared is the best way to ensure your project is tidy and attractive at the end of the day. Before you mix your cement, layout any decorations or words (a full size drawing is a good way to do this, any crude sketch will do) on a flat surface. That way you will simply have to transfer the design into the wet cement when the time comes.
2. Mixing the cement. This is the most important step in the process. Too much water will lead to a weak stone that is discolored. It will also cause water to seep into writing on the stone unnecessarily (although some of the will happen even if the water content is perfect). Too little water and you get a weak stone that will cure too quickly. Our rule of thumb at Milestones is two cups water to 7 lbs. of mix. In some places you'll find our box mix refills of cement come with 8 lbs. of mix. You'll have to adjust for that extra pound. The safest way is to mix the two cups of water with the full 8 lbs. and then add 1 teaspoon of water and mix thoroughly until the mix is the consistency of thick browny batter (you will need to push it into the mold, because it will not flow on its own). This "teaspoon at a time" method is the best way of ensuring a good cement mix.
PS - if you are making one of our 8" stepping stone kits (any Kids kit), you simply cut the equation in half: there are 3.5 lbs. of mix in these kits, so you use only 1 cup of water.
3. Add to the mold. This is an important step in getting a really professional finished product. Once all the mix is in the mold take a little extra time to get the concrete nice and smooth. Use the smoothing stick included, or some other smoothing tool you might have around the house, like a spackle. Just remember to clean it thoroughly with water before the cement dries on it - and make sure to clean it in a place where you don't mind getting cement residue (like the backyard). Shaking the mold just a bit will also help even the cement in the mold and flatten the surface.
4. Transfer your design. Now just move your design from the tabletop to the wet cement. Take care to put the decorations where you want them the first time so you won't have to move the pieces and mess up the surface of the stone. Make sure to add all decorations before you start writing or stamping any letters. Writing and stamping letters should be done about 15 - 20 minutes after the cement has been put into the mold. This will help ensure the letters are clear and crisp with minimum "seepage" from the surrounding cement.
Hint: when putting any decorations in a stepping stone kit, remember that cement itself is not adhesive. In other words, decorations only attache themselves to the stone if the cement is able to wrap itself just slightly around the edge of the decoration (or burrow into some irregularity on the bottom of the decoration. If decoration ever come out of the cured stone later, just glue them back in with any waterproof glue.
5. Let the stone cure. Our cement mix will take 45 minutes to cure beyond where you will be able to work with it, so make sure your design is in the cement before 45 minutes pcrafty!es. Then, you should wait 24 hours before moving the stone from the place where you originally poured the cement into the mold. Finally, you should wait 48 hours before putting any pressure on it. The stone will be at full strength within 7 - 10 days.
Good Luck - Arthur
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