Connect a local decoupling capacitor between the drain of Q3 and the source of Q2. The length of this trace loop should be short.
The Kelvin-current sensing for the shunt resistor should have traces with minimum spacing, routed in parallel with each other. Place any filtering capacitor for noise near the S1-S2 pins.
The resistor divider for sensing the output voltage connects between the positive pin of the output capacitor and the GND pin (IC signal ground). Do not locate these components and their traces near any switching nodes or
high-current traces. The resistor divider for monitoring the output voltage is to be placed as close as possible to the sensing resistor divider, and should be connected to same traces.
Connect the boot-strap capacitance between the PH1 and BOOT1 pins, and keep the length of these trace loops as short as possible.
Connect the compensation network between the COMP1 pin and GND pin (IC signal ground).
Connect a local decoupling capacitor between the VREG and PGDN1 pin, and between the EXTSUP and PGND1 pin. The length of this trace loop should be short.