alias +scores "net_graph 1; +showscores"
alias -scores "net_graph 0; -showscores"

bind tab +scores

ez

alias +showscoresandnetgraph "+showscores; net_graph 1"
alias -showscoresandnetgraph "-showscores; net_graph 0"

i think that will work

ninjas

alternatively here is a way to make it really small and out of sight, you will need to play around with the height value depending on your monitor resolution

alias netgraphsmall "net_graph 1; net_graphpos 1; net_graphproportionalfont 0; net_graphheight 1050"

it makes it very tiny and at the top of your screen the same size as cl_showfps