You can’t have an enticing story without your characters stumbling over obstacles. If you have previously made profiles, you will have some idea as to the type of obstacles you wish to include in your novel.
Consider the following:
What does your character want to accomplish?
Will that character be able to overcome the obstacle?
What is needed for a bad character to grow within the story?
It is the writer’s role to make life difficult for their characters, but knowing how those characters respond to difficult situations will help with your character’s development and credibility.
Don’t however, just throw obstacles in for the sake of it; plan carefully so that the obstacles are in relation to the plot, and that they are placed where they need to be to maintain the flow.
Consider the reactions of your characters when faced with a tricky situation – How has this obstacle made the character feel? And what will they do to overcome it?
Fear, anger, self-loathing, impatience, frustration etc.
Physical limitations, and the actions of the people around you.