It's easy to get softly textured walls by troweling a tinted dimensional compound on the walls and brushing over it before applying a rich indigo glaze.
What You Need
Tinted dimensional compound
Drill and mixing bit
Latex paint: indigo
Clean lint-free rags
Tint the dimensional compound with selected colorant or have paint store staff tint the compound for you. (If you are tinting the material yourself, mix the colorant into the compound using a drill fitted with a mixing bit.)
Working in 5-foot-square sections, apply the compound with a trowel in random arm-length X-shape sweeps. While the compound is wet, brush over it with a wallpaper brush using similar X-shape sweeps to create the subtle texture shown in the photo. Allow the brushed wall pattern to dry thoroughly, at least 24 hours.
Mix equal amounts of indigo latex paint and glazing medium. Again working in 5-foot-square sections, apply the indigo wall glaze with a household paintbrush in a large random X pattern over the textured walls. While the glaze is wet, wipe off some of it using a clean, lint-free rag, allowing the color to settle only into the crevices. (This creates the dark-on-light pattern.) Allow the finish to dry thoroughly, at least another 24 hours.