There are several ways to earn points and miles. Each method has pros and cons. The three main methods are the following:

1] Credit card sign-on bonus
The most lucrative way to earn points and miles is thru credit card sign-on bonuses. In general, when a credit card offers 100,000 points or miles as a sign-on bonus, this is usually an excellent offer and worth pursuing.

Personal Cards
If you are newbie, it makes sense to apply for certain credit card first due to a max limit on the number of personal cards, the number of applications and application timing restrictions.

Business Cards
There are no restrictions for business cards and credit card companies they don’t count toward your personal card total.

American Express
Sign-up Bonus Limit: Once per lifetime per card
Number of Cards: ~5
Other: None

Bank of America
Sign-up Bonus Limit: None
Number of Cards: None, but it is dependent on your total credit
Other: There is a 2/3/4 rule where you can only get 2 new cards in a 30-day period, 3 new cards in a 12-month period and 4 new cards in a 24-month period

Barclay
Sign-up Bonus Limit: None
Number of Cards: None, but it is dependent on your total credit
Other: There are some vague rules

Capital One
Sign-up Bonus Limit: One-time bonus
Number of Cards: 2
Other: There are some vague rules

Chase
Sign-up Bonus Limit: 24-48 month restriction with sign on bonus and within family of credit cards
Number of Cards: none, but it is dependent on your total credit
Other: There is a 5/24 rule where you automatically get rejected for any Chase credit card if you have opened 5 or more credit cards within 24 months

Citi
Sign-up Bonus Limit: Once per lifetime
Number of Cards: none, but it is dependent on your total credit
Other: There is a 24 month wait rule for opening and closing Citi cards and a 48 month restriction wait rule for co-branded Citi cards

2] Credit card spending categories
Using the correct credit card to earn the maximum points is the key earning lots of points and miles. The best credit card to use for each category is the following:

Air Fare

Hotel

Rental Car

Other Transportation

Restaurants

Groceries

Gasoline

Internet, Telephone, TV and Other Communications

Non-category

3] Actual Miles Flown
This is the hardest way to earns airline points and miles. On US airlines, you don’t earn one mile per one mile flown except for Alaska Airlines. You earn a percentage that is dependent on your air fare class and airline status.

For credit cards, you still earn at least one mile per dollar spent.