East Kent Goldings is a variety of Goldings grown in East Kent. Styrian Goldings are a number of hops grown in Slovenia, of which a large part are related to Fuggles (and some, like the super Styrians, apparently to Brewer's Gold). Mosaic is an absolutely wicked American hop. Flavour wise it is like a blend of Cascade, Citra and Simcoe (fruity and piney) which a funky sort of strawberry note.
The way I've worked with liquid extract usually is: add 1/3 to the beginning of the boil with the bittering hops, add flavour hops at 15m from the end of the boil together with the remaining liquid malt extract. Definitively go and add the Mosaic as dry hop, maybe some late on in the boil too. For something light around 3.8%-4.2% depending on the yeast, 3kg of light LME, 40g Goldings at the beginning of the boil, 20g with 15m from the end of the boil. After fermentation is over dry hop with 25g Mosaic. You can always add more hops or malts up to taste.