Melt your soap bases as per the instructions in a microwave or double boiler. Regardless of the melting method, it is recommended you keep your soap bases on a double boiler to keep them warm.
Weigh out 15g of clear melted soap base and 5g of white melted soap base into the paper cup.
Add royal blue soap colouring and mix well.
Pinch the rim of the paper cup to make a pouring spout and pour the soap base into the hexagon-shape section of the mosaic tile silicone mould.
To ensure all of the tile cavities are filled evenly, spread the soap base around with a rubber scraper and spray alcohol to break the surface tension and remove any bubbles.
Repeat steps 12-16 to make green square soap tiles, light blue circle soap tiles, and yellow triangle soap tiles.
Pour any remaining soap base into a paper cup to be used again later (optional).
Set the soap aside to set for 1 hour.
Once the soap is set, turn the mosaic tile mould over and push out the mosaic soap tiles onto the paper-lined tray while bending and flexing the mould.
Separate and sort the soap tiles by shape into separate piles.
Check that your round, base soap bars are set enough that the surface of each bar is hard to the touch.
Start assembling mosaic tile designs in the centre of each round bar. Add a border if desired.
Use a pair of scissors to trim the edges of the mosaic soap tiles (if necessary) as you go.
Use a breadboard and a sharp knife to cut the mosaic soap tiles down to different shapes if required.
Use a pair of plastic tweezers and a metal or bamboo skewer to carefully push all the mosaic soap tiles to exactly where you want them positioned.
Weigh out 70g (~2 ½ oz) of white melt and pour soap base and cut it up into small cubes. Include any leftover soap base saved from earlier if available.
Melt your soap base as per the instructions in a microwave or double boiler (for this part of the process a double boiler is recommended).
Scent your soap with fragrance oils or essential oils (optional).
Spray the surface of your mosaic soap designs with alcohol to help the soap layers adhere to each other.
With your melted soap base in one hand, and your spray bottle of alcohol in the other, gently pour the liquid soap base around the mosaic soap tiles to ‘grout’ them into place.
As you pour, spray the soap with alcohol to help it fill the small gaps between the mosaic soap tiles, and to remove any bubbles.
Clean up any white soap spilled on top of the coloured mosaic soap tiles immediately with a cotton bud dipped in alcohol.
Once all four soap bars have been ‘grouted’ pour any remaining white soap base into a paper cup to be used again later (optional).
Allow the soap bars to set overnight and then demould them by pushing from the bottom as you peel back the silicone mould.