The structure for the present factual conditional is:

If + present simple ( if clause) + will / be going to (result clause)

You can also you the modals may / might / or canwhen the result is not certain (possibility).

present simple

won´t

If you pack a few essentials in your carry-on youwon´t have to worry about your luggage.

So, to form the present factual conditionalwe use thepresent simple in the if clause and will / won´t in the result clause.

present simple

be + going to

If you check the luggage limits, you´re going to avoid the extra charges.

present simple

possibility

If you take a cab you may / might / can make it on time to the airport.

simple past would

If they flew more often, they wouldn´t be so airsick.

If they flew more often, they might not be so airsick.

In this case I´m using if + simple past because the reality is that they don´t fly very often and the result has to bestructurized with would + base form and if it´s a possibility with may or might.

The name speaks for itself with this structure.

The past unreal condional refers to something that is unreal in the past in others words it didn´t happenin the past and the result most of the time is a regretin the present.

past perfect + would + have + participle ( pres. perfect )

If I (had applied) for a visa, I ( wouldn´t have had ) hassles with theimmigration).

I didn´t apply for a visa, therefore I had hassles with the immigration.