Here are some exercises to make your feet stronger and more articulate. For all of these exercises, try 8-10 repetitions. Once you become comfortable with that many, add additional sets.
doming
Place your feet in parallel. Trying to keep your toes long (not scrunched). Dome your MTP joints up away from the floor. You should see the joints at the bases of your toes move up away from the ground, making an even rainbow of an arch from your big toe joint to your pinky toe joint. You should feel muscle activation underneath the sole of your foot. If you feel it all in your toes, you may be scrunching them too much!
point and flex
This one is self explanatory :). Sit with straight legs and find parallel, aligning the center of your hip socket, knee cap ankle and 2nd toe. Keeping your heel on the ground, straighten your legs fully and flex through your heels. Point long through your feet and toes without letting them veer in or out. Feel like each toe is making a long extension of its metatarsal. Repeat!
foot fan on ball
Place a pinky ball underneath your metatarsals, right before they become the ball of your foot. Keeping your heel grounded and knee stable, fan your foot from right to left. Use this motion to create more width and space in your feet as well as iron out any kinks you may feel underneath. Practice finding smooth motion and equal rage on both feet.
play the piano
Sit on a chair or on the floor and find parallel alignment with bent legs. Keeping the balls of your feet grounded, lift your toes away from the floor. Try to keep the heads of all metatarsals on the ground. Now try just lifting your big toes. Often times these toes will move in towards the other toes, but try to lift them straight up. Now try just lifting the middle three toes while keeping your big toes and pinky toes grounded. You may have to use your hands to keep them down. Now pick up all of your toes again and try to place one down at at time, starting with your pinkies. Make the motion smooth and try not to crunch your toes or let them veer away from the line of your metatarsal.
relevé
Stand up, keeping parallel leg alignment. Place a ball in between your heels. Place your hands on a solid surface for stability. Rise up on to the balls of your feet. Hold the ball and try not to scrunch your toes. When you rise up, try to do so by really going UP rather than merely shifting your weight forward. Keep looking for balance across the balls of your feet and think about making a connection from your sits bones to your heels. Make sure to stretch your calves after this exercise!