Miss Fortune and Sona work really well on Bot lane mainly because of their Ult's. Both of there Ult's effect champions in a certain area. The idea is too aim Sona's Ult on one if not both, if you can land Sona's Ult then Miss fortunes can engage her Ult. You should be able to pick up at least 1 kill out of this.
Early Game -
In the laning phase you want to go aggressive because when you have full vision of the lane it will be better for both of your Ult's when you can actually see if they go in brushes and so forth. It would be a good idea to hide in a brush and go in from behind because with the combo they still have to walk back to their turret in that time you can do a lot of damage and potentially get a kill if not gotten with the combo before.
Ganks -
If the Jungler comes Sona's crescendo should save you. Miss Fortunes passive will allow her to get away and her W will slow them, Sona can give movement speed if needed.
Late Game -
In late game both of their Ult's will work really well in zoning out champs. For example you start the fight with Sona's crescendo then follow up with Miss Fortunes Ult. Not all of the 5 of the other team will be in that crescendo so you will be able to pick off the ones that are trapped in the Ult and have the remaining 2-3 champs to kill with your 5 full health team mates. That should help you win that fight because they will be out numbered.
As long as both Ult's are up and you can get them both off at the same time this should work without any problems. It would be a good idea to have good communication with the other player as it will be key in timing!
