It's not that far... Cross to the other side and walk the path right the way through to Falmer... 15/20 mins walk max IMO.
Or
Catch the bus from right outside the Newmarket and it's one stop to Falmer or two stops to Falmer Station. No real issue whichever way you decide to go.
Or
Catch the bus from right outside the Newmarket and it's one stop to Falmer or two stops to Falmer Station. No real issue whichever way you decide to go.