Design a 20-base (single guide) sgRNA sequence to cut the gene (PAM) using CRISPR/SpCas9 between the 7th and 20th amino acids coding sequence. This is in the beginning of the gene, but not at the very beginning. sgRNA sequences will be designed as DNA, cloned into a vector, and then expressed as RNA. So, you need to design the dsDNA construct to synthesize to clone into a vector.