Answer: It is probably your natural vaginal lubrication that is flowing from your vagina. Your vaginal lubrication should be clear and slippery, like uncooked egg whites. Many women get very "wet" when they are sexually aroused. It is normal for women to create a "wet spot." Your vagina may produce too much lubrication, reducing the amount of stimulation you and your partner experience. I don't know of anything that can be done to alter this.
It is also possible that some of the fluid is coming from your urethra and is called Female Ejaculation. This too is perfectly normal.
The illustrations at the beginning of the article about the anatomy of the vagina may help your partner achieve penetration easier.
Your vaginal and pelvic muscles may be a little too tight. When you masturbate, you might want to start inserting one to three fingers into your vagina to help stretch them. You might want to learn Kegel exercises so you can relax your pelvic muscles to let him in.
Do not place too much emphasis on intercourse. On some days only masturbate together, give each other a full body massage, or engage in oral sex. You will both likely find sex more enjoyable and less challenging if you do.