Coronavirus disease MESHD 2019 (COVID-19) is undoubtedly the most challenging pandemic in the current century with more than 253,381 deaths MESHD worldwide since its emergence in late 2019 (updated May 6th, 2020). COVID-19 is caused by a novel emerged coronavirus named as Severe Acute Respiratory Syndrome MESHD Coronavirus 2 (SARS-CoV-2). Today, the world needs crucially to develop a prophylactic vaccine scheme for such emerged and emerging infectious pathogens. In this study, we have targeted spike (S) glycoprotein, as an important surface antigen of SARS-CoV-2, to identify its immunodominant B- and T-cell epitopes. We have conducted a multi-method B-cell epitope (BCE) prediction approach using different predictor algorithms to discover most potential BCEs. Besides, we sought among a pool of MHC class I and II-associated peptide binders provided by the IEDB server through the strict cut-off values. To design a broad-coverage vaccine, we carried out a population coverage analysis for a set of candidate T-cell epitopes and based on the HLA allele frequency in the top most-affected countries by COVID-19 (update 02 April 2020). The final determined B- and T-cell epitopes were mapped on the S glycoprotein sequence, and three potential hub regions covering the largest number of overlapping epitopes were identified for the vaccine designing (I531–N711; T717–C877; and V883–E973). Here, we have designed two domain-based constructs to be produced and delivered through the recombinant protein- and gene-based approaches, including (i) an adjuvanted domain-based protein vaccine construct (DPVC), and (ii) a self-amplifying mRNA vaccine (SAMV) construct. The safety, stability, and immunogenicity of the DPVC were validated using the integrated sequential (i.e. allergenicity, autoimmunity HP, and physicochemical features) and structural (i.e. molecular docking between the vaccine and human Toll-like receptors (TLRs) 4 and 5) analysis. The stability of the docked complexes was evaluated using the molecular dynamics (MD) simulations. These rigorous in silico validations supported the potential of the DPVC and SAMV to promote both innate and specific immune responses in the animal studies.