Clean your surface (both sides) with mild soap and water or alcohol, avoiding the painted area. Let dry.
Paint the base with white paint and let dry. You'll only need one layer.
Once the paint is dry, rub a wax candle piece anywhere on the surface you'd like to add the distressing. I did it on the edges and then a bit on the sides and the top.
Paint the khaki paint over the top of the wax and warm white paint. Let dry. Add a second coat if needed and let dry.
Using the sandpaper, remove areas of the paint where the wax is to reveal the color below and create a distressing effect. Keep sanding until the desired affect is achieved and wipe away the dust.
Remove your pressed flowers from the package and choose the ones you'd like to use in your design. Use the tweezers to handle the fragile items.
Choose a side, and pour a few tablespoons of Mod Podge onto the surface. Begin swirling the Mod Podge in circles with your index finger on the surface.
Work quickly, making sure to cover the entire area with swirls. The end result should be a light to medium layer of Mod Podge on top of the surface.
Place the dried flowers into the wet Mod Podge swirls using the tweezers and press down. Continue until the design has covered the surface. I did a second surface as well, both with a single layer of flowers.
Let the Mod Podge and flowers dry. This process is going to take several hours in some of the thicker areas, and maybe overnight, but everything should dry clear. You can pop any pockets of decoupage medium with pins and squeeze gently to help dry.
Seal the surface base with Mod Podge and let dry, then repeat. Let dry completely before displaying.
Notes
This project can take time to dry so you'll want to have patience!