Important. First of all you need to remove the Online Data folder. "The reason why the trainer may be working buggy in some cases, is because those who are constantly connected to the 2k servers, will constantly be receiving new updates. These updates will be stored in your "Online Data" folder under C:\Users\(Useraccount)\AppData\Roaming\2K Sports\NBA 2k14. These updates have obviously changed several memory addresses and have resulted in making the tool somewhat buggy. This has been hinted before in this thread, but If you'd like to enjoy all the features of the trainer, make sure you're NOT CONNECTED to the servers and completely REMOVE the Online Data folder." © PeoplesChamp, NLSC forum. Anyway, after all manipulations with trainer you can put Online Data folder back.
So, what we need:
1. Fantasy Star Trainer by Aleczou. (I'm using v1.3)
2. Your preferred roster.
3. Bit of patience.
Okay, let's start.
1. Load your preferred roster and go to "Options" > "Manage Roster" > "Rosters" and edit your preferred player that you want to create for MyCareer. Save all changes. Or you can change nothing and leave everything by default. From main game screen go to "Features" > "MyPlayer" > "Edit MyPlayer" and set the skintone and any name ("Lol Lol" for example), it doesn't matter.

2. Start new MyCareer. Play (or skip, use trainer option) Rookie Showcase. Go through the Pre-Draft interview. Get drafted by any team except the one which there is your preferred player. For example, if you want Paul George - don't get drafted by Pacers, want D-Rose - don't get drafted by Bulls, ect. Save all changes manually. Close the game and start it again. Load your MyCareer save file.
3. On main MyCareer screen (it's where calendar, tweets, your minutes, ect.) you minimize the game and start the trainer. Push LeBron icon (screenshot) "1.", search your preferred player by name (screenshot) "2.". Right click on his name - it call the pop-up menu. Click on the last line of this menu (screenshot) "3.". Maximize the game and save all changes manually.

4. Now you need to change the time in the rotation.
1st Method.
From main MyCareer screen go to "Team" > "Rotation". Minimize your game again, start the trainer. Push the "MC" icon (screenshot) "4.". Set any minutes you want (screenshot) "5.". Check the small checkbox. It will lock your minutes (screenshot) "6.". Maximize the game, now you can see your rotation time has changed. Go to main MyCareer screen, now you get a message like "you cracked the starting lineup" or somthing... Blah blah blah, just skip it. Autosave will save all changes.
2nd Method. (if first method doesn't work for you)
Load your MyCareer. On main MyCareer screen minimize your game, start the trainer. Push the "MC" icon (screenshot) "4.". Set any minutes you want (screenshot) "5.". Check the small checkbox. It lock your minutes (screenshot) "6.". Maximize the game and go to "Team" > "Rotation", and then go to main MyCareer screen again. Now you can see your time has changed. Save all changes manually.

5. Now you need to remove player that you created before. Minimize your game and run the trainer. Search your previously created player by name ("Lol Lol" for example, like a said earlier) as you did in step 3. Left click on his name and push the "Player Info" button (screenshot) "7." Then go to "Team 1" and "Team 2" options. Click on small arrow, scroll down to the bottom and choose any ********** team (screenshot) "8.". (I don't know what team is it, but it method works, previously created player is completely removed from the current MyCareer roster. If you know a simpler way - let me know.) Save all changes manually.
For another method to remove the player, you can just make him a FA and lower all his ratings to 25 (use trainer options). So no one of CPU teams doesn't sign him, i guess...

Hooray! That's it! You are done!

For those guys who say it does not work. Try this.
JohnyFirst wrote:Onlyforward wrote:If you will ever want to make real player again, make sure you delete shoes,cache and online data folders(in my case it worked) before starting the game, then after you get drafted, like you said, deleting folders is also advisable. So I deleted everything again before starting the game 2nd time and it worked. And I also started the trainer before the game. Good luck.
Thanks for the info, I'll keep it in mind next time. And btw my Derrick Rose wears my edited Adidas DRose 4, so you can try to make a mycareer player without deleting your shoes. I hope now we will have no problems with this.
A lot of guys ask here or via PM: "Why my trainer doesn't work?" I. DON'T. KNOW. Please, ask your questions about MyCareer creating process, not about why trainer doesn't work and stuff like that.
Thanks to guys from NLSC forum for the important information, and of course to Aleczou for the trainer. More info about the trainer you can find here -> (viewtopic.php?f=153&t=92987).
Hope this guide will be useful to someone...
From Russia with love!

Cheers, JohnyFirst.