A jacket assembly guide for assembling a jacket structure is provided. The jacket structure includes a plurality of legs, a plurality of connecting braces and a plurality of node elements arranged on the legs for connecting the braces to the legs. The assembly guide includes a plurality of supporting towers for supporting the plurality of legs such that a supported leg is held in a position corresponding to the position of that leg in the assembled state of the jacket structure. The assembly guide further includes a plurality of connecting devices for releasably connecting one of the legs to one of the supporting towers.