Developing sustainable alternatives to conventional cement binders is essential to preserve the environment against pollution and exploitation of natural resources. In this regard, utilizing geopolymer (GP) composites is one of the best options. However, various factors influence GP functionality. The curing method is one such factor that directly influences the establishment of the polymeric network in GPs. Similarly, superplasticizers (SPs) play a vital role in controlling the workability of GPs without altering their water-to-binder ratio. Determining the suitable curing condition and plasticizer dosage for a given precursor is important as it directly controls GP’s fresh and hardened state properties. Hence, in the current study, GP mortars prepared with fly ash and ground granulated blast furnace slag (GGBS) were examined under various conditions, including water, ambient, and oven curing at 60 °C. The evaluation focused on the influence of the curing process on compressive strength. Additionally, the workability and strength were evaluated by altering the quantity of polycarboxylate ether-based SP from 0 to 3% of the precursors. It was observed that the curing conditions are highly dependent on the type and chemical content of the employed precursors, and oven curing is unnecessary when the GGBS is abundant. Optimization of plasticizer dosage for compressive strength and workability indicated an SP dosage of 1.5% of the weight of the binders.