1) Every man is different, experiment with speed, tension, depth etc.
2) Listen to his breathing when doing the deed, if you are doing something he really likes, you will hear it in his breathing.
3) let him know you LIKE what you are doing. Just doing it without enthusiasm or robotically is a sure buzzkill.

That is jus a few of the things that make a blowjob nice, there are others . less

1. We love enthusiasm and want you to enjoy it as much as we do. Last thing we want is for you to feel pressured, forced, or not enjoying it.

2. Please make sure that the head of the penis is properly lubricated try some premium flavored lube it does wonders and some of the brands taste amazing. Start with a swirling lick from the base of the shaft and slowly go to the tip of the head of the penis. Think of an ice cream cone. The head of the penis chaffing against dry skin (hands, lips, and even inside the cheeks if not enough saliva is produced) can be extremely painful and a mood killer.

3. Sounds! We love when you women make the occasional moaning sound when performing oral sex. It makes us feel more connected to you and makes us believe that you are enjoying it to.

4. Eye contact! Men we are visual creatures. We love when you make eye contact with us as you perform oral sex.

5. Communication! Stay attentive to our body movements, heart beat, audio queues, and breathing. This applies to Men as well, if you are enjoying a particular way something is being done let your partner know. If something is causing discomfort let your partner know. If your partners doesn't know how it's feeling they cannot make it more enjoyable for you. less

Self explanatory.

Women can tend to think they are great at oral sex because guys with a mouth on their cock will say anything to keep it there.
(Personally dont know if the same is true when men are together)

So, what three things would you really want a partner to know? less