Whatever your mosaik style, this is an interesting technique for the 'in between' parts or 'grout' lines.

1: Create the base of the mosaik by cutting an appropriate mounting surface from adhesive backed paper or use a 'sticker making machine' to make the back sticky.

2: With sticky side of backing facing up, stick the 'tiles' down and leave a small gap for 'grout'

3: When the mosaik is done, sprinkle embossing powder on the exposed adhesive and gently shake off excess.

4: Heat the embossing powder and watch the effect take shape.