Once you have done a few, the Rose Bud is easy to work.
When the pattern calls for it, you work 3 sc in the back loop only (BLO) of the next st.
For easy access and finding, place a stitch marker in the third loop in the first of those three single crochets.
Turn your work by 90° (right-handed: clockwise, left-handed: anti-clockwise).
Work 4 sc in the front loop only (BLO) of the same stitch, continuing to turn your work clockwise/anti-clockwise around as you go.
Close the Rose Bud with a slip stitch in the third loop of the first sc (with the stitch marker, if you chose to use it).
Continue in the next stitch.