How do you obtain a star rank in Mario Kart Wii?

I would like to know how to get a star rank for your profile in MKW. It says what your overall rank is in your profile settings, and mine says A, when clearly I get star to 2 star ranks in grand prix cups. I just want to know why it thinks I suck so much, when I clearly am amazing. Unless it also includes the way you play in other modes like time trials or battle modes. I have currently unlocked 12 expert staff ghosts for all 12 tracks in Mushroom, Flower, and Star Cups. I have obtained all golden trophies for every cup in 50 CC with a 2 Star rank for each, but I have only 5 golden trophies with a 2 Star rank for those 5 cups in 100 CC. I have unlocked all cups and tracks of course. I have unlocked Rosalina, Birdo, King Boo, Diddy Kong, Baby Daisy, Baby Luigi, and also Funky Kong. I have finally unlocked the Magikruiser, Tiny Titan, Cheep Cheep Charger, Super Blooper, Piranha Prowler, Shooting Star, and the Spear. So, am I doing anything wrong or what?

Information from GameFaqs

Guidelines for getting a 1-Star Rank:

Trying to get a 1-Star Rank allows for some leeway, but not too much. To earn a 1-Star Rank, you'll still have to play well.

-You are allowed to bang into walls (1 or 2 times)

-You are allowed to bang into obstacles (1 or 2 times)

-Stay on road as much as you can (Off-roading is allowed 2 to 3 times without a boost)

-Try not to fall off the track (Once is allowed, twice almost guarantees a non-Star Rank)

-Do as many tricks/tactics as you can. Drift Boost, Snaking, Wheelie, etc. (This is a rumor, but it may help)

-Stay in first for a good amount of the race

-Try not use items to catch up to other players (once is allowed. Ties into the above reason)

-Finish as fast as possible

-You must get 53 points or more as your grand total

Guidelines for getting a 2-Star Rank:

Trying to get a 2-Star Rank is obviously harder than trying to get a 1-Star Rank. It allows for little leeway.

-Try not to bang into walls

-Try not to bang into obstacles

-Stay on the road as much as you can (Off-roading is allowed 1 to 2 times without a boost)

-Try not to fall off the track (maybe once, but it almost guarantees you a 1-Star Rank)

-Do as many tricks/tactics as you can. Drift Boost, Snaking, Wheelie, etc. (This is a rumor, but it may help)

-Try to stay in first for most of the race

-Try not to use items to catch up to other players

-Finish as fast as possible

-You must get 55 points or more as your grand total

Guidelines for getting a 3-Star Rank:

Trying to get a 3-Star Rank is no doubt harder than getting one of the two previous Star Ranks. It allows for almost no leeway.

-Try not to bang into walls

-Try not to bang into obstacles

-Stay on the road (unless you have a boost item to allow you to travel off-road)

-Try not to fall off the track

-Do as many tricks/tactics as you can. Drift Boost, Snaking, Wheelie, etc. (This is a rumor, but it may help)

-Stay in first for much of the time in races

-Try not to use items to catch up to other players

-Finish as fast as possible

-You must get 60 points as your grand total

facepalm! I said how to do it to make your profile have an overall rank of star or higher; not the grand prix cups!

It takes your average ranking from the Grand Prix. So once you get a star average in all of them you get a star ranking, so on and so forth. I have a three star rating on all cups so I have three stars on my file. You just have to improve your rating in each up and it'll go up on it's own.