Play with friends. The required adjustment in playstyle for random teammates may be to high to expect reasonably. If your unable to provide individual impact consistently (implied heavily by the fact your requesting assistance in doing it better)
With just a duo, you will find Having an "ADC" Run
would provide sustain and lower your Time to significant item power spikes inherent with
.
Further you can try swapping out your Bot with a Champion that has a stronger early game impact then traditional ADC classes. There are options for ranged DPS viable in top lane matchups. So with 2 friends you could run ADC top and a Cheese off meta kill lane bot. I think some reliable DPS with CC would be ideal.
for example, Plus he could roam using his R at which point Fiora support should snag some CC and scale quicker.
As there are lower options in your usefulness early compaired to a massive # of available options when running this as a support it should be treated as a cheesing strat. You want to abuse a powerspike on your kill potential with Fioras kit + a consistant factor to enable that kill pressure. Duoings the best way to achieve this. 3 players would be better as you can create a comp that accounts for this strategy with a majority of your team and also not create negative impacts by demanding excessively dramatic adjustments to standard player play patterns.
Far as In lane. Learn how to drop Aggro for passive on bad spawns. Walking away to reapply passive in directions you can realistically target will give you a bit more damage and a bit more sustain from using your Q casts to harass.
Your income item should be related to how your planning to lane.
DO NOT UPGRADE TO T3 ITEMS AS THE STATS ARE SUBPAR FOR THE GOLD. What you want on fiora is going to be better gained from investing that gold elsewhere. T2 is fine, more income, free vision. T3 is a trap, avoid it. Engage off CC for your R and focus on hitting the farthest possible marks, as a champion in bot trys to kite you they will position away. if they cant take your lane in a 100 to 0 attempt they are forced to try and flee towards their tower. if you can trigger R then you have a very strong zone heal you can fight in and the opponent will need to maneuver away from it.
Body block dramatic CC ability's, strive to parry them, especially if they have long CD
R for example.