Dive shoes with stiff sole
Your traditional soft sole diving shoe will offer you absolutely zero ankle support as you walk across loose gravel. If you need to cross gravel or rocks, get something with a stiffer sole.
Clip off fins
If you run an SPG, you can string your fins through the SPG hose and then clip the SPG to your left waist D-ring. If you do not run an SPG, you can also use a large double-ender to clip the fins to your hip or chest drings.
If you have the fins in your hands and you enter the water up to your waist, then how are you going to put your fins on without letting go of one of them and they float away or sink? Just clip them off and remove one at a time.
Clip off primary regulator
This will be a bit difficult if you use the traditional hose routing technique, however if you are using sorta-long hose or long-hose...you can use the boltsnap on the primary regulator to stow/clip-off the regulator to your right chest d-ring. In an emergency, such as falling over in the water, there is a regulator on a necklace under your chin.
Pre-walk additional equipment
Don't try and save yourself a trip and carry everything at once. You want your hands free as you transport whatever back gas you are carrying. If you have a pony bottle or a DPV or other additional heavy equipment...take that down first. Lay it next to the water. And then go back and get suited up and walk your main gear to the waters edge.
Dump weights in hand
If you have clipped off your fins and you have your mask on your head already...then your hands are free. Walking on sand, gravel or rock while having 40lb of gear on your body isn't always great for your ankles or your stability. One way to reduce some of that feeling of being "top heavy" as you walk is to put any ditchable weights in your hands. Typically you can drop them if you feel like you are about to fall over and you can always put them back in once you get to thigh level in the water.