Let's assume your kit gives the right level of bitterness. What you want to add is the fresh hoppy flavours that a kit can't really do. I would get a bag of American hops from the list above and make my kit as per the instructions but substituting pale malt extract if you are advised to use sugar. You can add a bit more extract than the sugar recommendation, 'cos it's not as "strong". Add 1.2kg instead of 1kg of sugar maybe.
When the kit stuff and extract are in your pan and have reached a boil, take it off the stove and allow to cool to around 80-90C. At this point add 30-40g of your chosen hop and allow to steep for 20 mins. Then sieve the panfull into your FV with a sieve, collinder or piece of nylon curtain material to collect the hops. If the latter, do it whilst the family are out, then thay'll never know:-D
After the fermentation has calmed down after a week or so, add another 20-30g of hops dry and leave 'til the brew is fermented out and looking fairly clear, usually about 14 days. Syphoning never seems to cause me a problem when I dry hop like this. Prime, bottle, wait.............................................and enjoy.