Both of the ladies pictured above are level 11 and are not members of a club. This is where the similarities stop. I can guarantee you that the lady on the left gets dueled almost every hour while the lady on the right does not. Imbalanced skills are often the culprit behind fashion duels. To prevent imbalanced skills it is important that you practice your skills equally. To save on money you can leave Style for last BUT do it before level 15. Trust me when I say you'll get plenty of opportunities to increase your Style skill. By the way the clothes in the Mall aren't going anywhere so really you can leave them for last. This is of course not the case for events when there are special stores.
Training your pets is super easy relative to the other skills. Just do it now and do it often.
{Guide to Earning Dollars, Diamonds, & Emeralds}
You can earn more money as you level up through a higher apartment income and a better job through FTV. Also, as you level up the amount of dollars you get from converting diamonds increases. Despite this, you shouldn't level up just to make more money if it means that your Lady will be weak. It's better to just duel for the extra cash you need now and work on your skills.
Dollars
There are three main ways to earn dollars in game:
Sending your Lady to work
Winning duels against other Ladies in the Fashion Arena
Income from your Apartment
You can also earn dollars by:
Winning duels against Supermodels
Completing missions at engagement parties
Converting diamonds to dollars
Emeralds
There are two main ways to earn emeralds in game:
Participating in photo sessions
Winning duels against Supermodels
You can also earn emeralds by:
Inviting friends to play Lady Popular and get emeralds when they level up, buy diamonds, and when they recruit more friends
Completing missions at engagement parties
Winning them in certain events
Diamonds
For the most part, you must buy diamonds with real money. There have been on occasion when the game developers have given us free diamonds due to server issues or during a celebration like International Women's Day. Again diamonds 99% of the time are bought with real money.
You can also earn diamonds by:
Spinning the daily wheel and landing on the 3 diamonds prize