How one can know he has syphilis?

What syphilis is?
Syphilis is a type of STD risks or sexually transmitted diseases (STD), caused by a spiral shaped bacteria, Treponema palladium.

How one could be aware that he is suffering from syphilis?
It leads to two stages:

1st Stage:
In its primary stage there appears some kind of abrasions like sore, also known as Chancre. These abrasions could appear on genital skin, rectum or in mouth. Such abrasions are like round firm sore, that doesn’t hurt on touch and doesn’t have burning sensation too.

2nd Stage:
Usually it heals after 4 to 6 weeks and goes to latent phase and patient feels that he has recovered and is healthy, but in fact he now is suffering from acute stage of syphilis.

Kissing can spread HIV....it is true?

True, kissing could spread HIV.  Spreading of HIV and STD risks are not limited to only oral, vaginal or anal sex with infected partner. When a normal person who is not yet effected with HIV, kissed by an effected person, who has lesions in his or her mouth, whether they are in tongue, in oral mucus or in gums, too, could make that normal person, an effected person who would afterwards acquire HIV or other STD risks from the infected person.

Does Anal Sex and Oral Sex can cause STD?

It is false assumption that, oral and anal contacts do not cause STD's and STD risks. If your partner has lesions in his or her skin, these STD's and STD risks can be transferred through these lesions.

How one could be aware of the fact that he has caught Sexually Transmitted Disease or STD?

It is not a troublesome job at all. Each of us must consult a doctor when it is founded that:
STD risks #1:  Any abnormality occurred in your genital skin
STD risks #2:  Any kind of abnormal feeling during sexual activity
STD risks #3:  Any abnormal secretion from penis or vagina
STD risks #4:  Any urinary disorder
STD risks #5:  Burning sensation
STD risks #6:  Pus like discharges with urine

Sexually Transmitted Disease or STD

"The infectious disease that can be transmitted through intimate contact among individuals"
Including
Vaginal, oral and anal.