Firstly, you have to pray before the interview.. Secondly, you have to comport yourself very well during the interview.. Eye contact with the person that will interview you is very important. Don't panic and don't rush any question asked you, take is slowly. One at a time.
Thirdly, go along with anything you can lay your hands on. If you a thousands different pictures, go with it. Call history, facebook chat, whatsapp chat/call, traditional wedding pictures if there is any, court wedding and white wedding pictures. If she did change of name after the wedding, go along with the evidence.
If both of you do help each other in monetary aspect, print your statement of account and indicates where her reflects on it.
Do you upload your wedding pictures on facebook or any other social network, if yes print it out where people are congratulating both of you after the wedding, print the post/pictures and people's comments on it.
If there is any of your pictures that any of uploaded on facebook and tagged each other, friends comments on it. Kindly print it out, a support letter from the both parents are very important.
Do you have any tickets where both of you travel together? Go along with it if you have any, anything you think that can prove that your marriage is real just go with it.
For you to get pre arrival shows that you have pass eligibility, your ppr will depends on the outcome of the interview.
Know when to disagree with him/her but do that politely, prove to him/her that your marriage is real. That age is just a number.
Lastly, study the form that she filled for you. Majority of the questions will come from there..
How did you met her, who visited each other first, how did she travel to Canada, where is she working, how much is she earning, what's her position in her place of work, her house address, what was she doing when she was in Ghana etc.
It will be of good if you can answer each question with date, month and year. Study that form very well and don't forget to comport yourself, prayer is the key.
Good luck