As a confessor, I have been debating what to contribute to this thread since there are several points.
I HATE getting in the nitty-gritty details
Please don’t go into extreme detail. It isn’t necessary and can be counter-productive. It can also border on the lurid, depending upon the subject. A confessor will instinctively hesitate to stop a penitent in mid-exposition as he is trying to piece together from the words being used what the penitent is confessing…however, there can be occasion when the priest actually would stop the penitent if the detail is gratuitous.
To name the sin, and to give a number if the sin is serious, approximating if there is doubt as to quantity, is what is needed…not detailed description. It can be daunting and even traumatic to the penitent and it’s immaterial to the confessor. It’s normative for a confessor, if he doesn’t understand, to discreetly ask for clarification.
If any detail makes clear an increase in the sin’s gravity, than the detail should be included.
The gravity of the sin is normally established relatively easily. “I had sex outside of marriage” tells me instantly the gravity…the sin is mortal in the absence of a mitigating factor which, if present, should be mentioned.
If there is something that alters the
nature of the sin, that needs to be confessed. “I had sex outside of marriage” is compounded if one adds: “I had sex outside of marriage with a married person” or again “I had sex outside of marriage with a married person and it was against her will.” I am absolving different things among those three statements and the penitent is confessing different sins among those three declarations.
Otherwise, when one is dealing with an action, it is not necessary to begin dissecting the act into its individuated elements, even though the constituent acts would themselves be serious sins if they were done on their own. And so, if one commits the consummated act of adultery, it is sufficient to say: “I committed an act of adultery” without explaining the act began by the willful lusting for the person and then the seduction and then describing each ensuing act unto its final consummation. If, on the other hand, it stopped short of being consummated, then one can confess what act occurred.
Thus, for the poster who asked about the oral act, if that is what happened and it did not proceed further it would be confessed using the term you wrote; if that was one aspect of a broader act of fornication or adultery, the part is included in the whole and that need not be confessed separately but would be absolved in confessing either an act of fornication or adultery which included that.
Keep in mind that the more detail you give in confession, the more grace you receive
This is really not a maxim to apply in confession. It will turn receiving the sacrament into a session of spiritual direction, if the penitent begins a complete exposition of conscience surrounding the named sin and its various circumstances and aspects contributing to it in great detail. The sacrament absolves sin, restores sanctifying grace, and gives actual grace.
You should just say, “Father, I’ve committed sins against the sixth commandment, would you kindly question me?” Then he can ask you for relevant info
Asking the priest to assist you in confessing is a mechanism to be used when you don’t know how to examine your conscience. If you violated the sixth commandment, you know what you did that violated it and should say it. It can be said by the penitent in a matter of a few words. Why make the confessor go through every permutation that the sin can take by a series of questions, which is what you are asking the confessor to do? The logical first question is the simple one: “What did you do?”
Mortal sins should be confessed in number and kind so your priest knows how attached you are to that sin and it helps you avoid the sin in the future by bringing the frequency with which you commit the sin into your consciousness. We may not realize how much we sin until we actually keep track. If you do not know the exact number of times, it is OK to approximate with words like, “often”, “frequently” or “a few times”.
Actually, it is not in order for me as the confessor to know how attached someone is to the sin…the giving of a number for serious sins is so that each iteration of the sin is brought to the sacrament. In the case where it is not possible to know the number, then we should approximate. I actually favour adding “approximately” at the beginning of doubt; thus, if you have any doubt, you add approximately, which covers a greater number within reason. It allays doubt.
“Often” and “frequently”, however, are of the most minimal value and the last possible resort; often or frequently could be several times per week or several times per day. It’s better to use a reference such as “never more than daily” or something that allows a number, however vague, to be posited.
A penitent is bringing to the sacrament the sins he committed in order, through the power of the keys, to be absolved of them. Confession should be integral in so far as it involves serious sin.
It is one thing to say I am sorry for the lies I have told since my last confession, presuming they are venial sins. It is another matter to bring to the confession the serious sin of committing perjury in which you have sworn to God that the words you spoke as true were, in fact, a lie. To do this five times is to bring to the sacrament, for absolution, something different from lying under oath one time; the former is bringing five separate mortal sins and, of course, the sacrament of penance is the normal way for the forgiveness of each serious sin. If there are multiples of the sin, each should be covered in the articulation…but again according to what is humanly possible.
Call me a glutton for punishment but, I confess face to face, whenever possible. There is something downright humiliating about having to look them in the eye and to confess something of this nature! 
I want to walk a righteous path with God as much as a sinner like me is able. This helps me!