DIY Glycolysis

Step One - Coupled Phosphorylation and Oxidation of Glucose

May be Possible but is Undesirable.

That could be done. The aldehyde group of glucose could be oxidised and phosphorylated with inorganic phosphate to capture the energy. However, if you split glucose into two first you can do this type of reaction on both halves later and double your money! Concentrate on making two identical molecules of triose from each mole of hexose, then think about capturing energy.