It says in the pattern that you need to continue working the front piece according to the chart. It is important to position the center of the chart in the middle of the front piece, so the pattern is centered and symmetrical
Which means, when you start on the right side of the front piece, you first work the last 4 sts of the chart (from the right to the left), then the whole chart (24 sts) from right to left, and then start from the beginning again so you get the 13th st of the chart in st number 41 on the front piece. Continue the rest of the chart on the other side of the arrow and start from the beginning of the chart again, continue until there are no more sts on the front piece.
If you work in the round and have the same pattern on the back piece, continue here in the same way. Start with the same st in the chart as in the front piece, work from the right to the left, just like in the front piece.
If you work back and forth, start from the wrong side on the next row in the chart, with the st over the st you finished with and work according to the chart from left to right.
See two models where this technique is used:
DROPS Extra 0-816 / DROPS Extra 0-817