I’m assuming this question is about YOUR mom.
The best way is to be respectful and attentive to her needs and desires. That excludes spying on her when she expects privacy, taking her things without her permission, sticking your genitals in her face uninvited.
Each situation is different. We don’t know her. You do. You know your history with her, and your personalities.
How is her stress level these days? If she’s stressed out, or tired out, she’s not going to be feeling very sexual, most likely. So make her life easier. Take care of chores and errands she needs done.
Seducing her is going to be much the same as seducing another woman her age. The big differences are that you already know and love each other, which is an advantage, and that she may have internalized societal prejudices against doing this, which would be a disadvantage. Please note that seducing someone isn’t about making them do something they don’t want to do. That’s a big no-no. It’s about letting them feel your interest, and inspiring in them the excitement of getting sexual, and maybe romantic.
As with anyone else, all along the process, you need to pay close attention to what she says, how she says it, her body language, etc. If she doesn't want to do something, you need to back off and respect that.
If you do these things in the right way, the worst that happens is she thinks she has done something wrong to cause these feelings in you, and you can assure her she hasn’t done anything wrong. Or she might think you need therapy. But that’s the worst case scenario.
On the other hand, she might already very much want something, but has been waiting for you to make a move (for various reasons, including you being the child, you being the male if you are, or others). Or, she might not realize she wants it until she’s given herself permission to think about it. Either way, she might hold back and want you to make a move. Or, somewhere along the process, she might make a move because she’s received enough signals or hints from you.
You're probably going to need a combination of both talk and action.
On the talk front, get her to talk with you about sex and relationships. The more she talks with you about sex, the better! Encourage her to talk as much as you can. Listen closely to what she says and how she says it. If you can get her to talk about what turns her on, great, especially if it includes people of your age and gender. Likewise, you can indicate that you are attracted to some people of her age, gender, body and personality type, etc. (you might even want to describe her in way she’d recognize).
As you have these conversations, you can bring up the topic of sexual limits and taboos, including "forbidden" relationships. For example, cousins. You might even ask her if she has ever been attracted to someone or fantasized about someone who she “wasn’t supposed” to think about that way. You can then bring up sexual relationships between mothers and sons. If her reaction isn't negative, that's a great sign. If you need a "reason" to bring up such topics, you can say the topic came up in a dream you had, or an article, story, television show, or movie you saw, or even that someone you know brought it up.
Throughout all of this, you haven't actually said that YOU want to have sex with HER. She might have figured it out, but since it hasn't been said, she can still cool things down if she’s not interested, with minimal embarrassment, and you can still deny, if she has a negative reaction, that you wanted to have sex with her.
As far as action, you want to increase the emotional and physical affection between the two of you.
Give her compliments. Flirt with her. Joke with her. Use terms of endearment, as appropriate ("Hey, Love...", "Honey", “Beautiful,” “My Dear”). Compliments should indicate that you recognize what she has to offer as a romantic or sexual partner, but not be so crude as to turn her off. Flirting can include smiles, winks, lingering looks (especially up and down her body), gentle and light touches on her arm, etc.
Give her more, longer, and tighter hugs, from both the front and behind. You might want to let your hands move as far as she’ll allow. Give her more, longer, and more suggestive kisses. Look for excuses to be close to her and touch her, even if just in passing, like a touch on the back, or the back of the neck, or the behind, depending. Offer backscratches, neck rubs, shoulder rubs, leg rubs, massages, or anything else that will get your hands on her.
You need to get her alone, relaxed, and feeling affectionate playful, and sexy. So, date her. Dates can be at home. It is setting up what will be an enjoyable time for her so that the two of you can spend quality time together, alone. Making or buying her favorite dinner, and/or having finger foods she likes that you can feed each other, and some wine (as long as neither of you is a problem drinker) can be great, along with cuddling up for a movie, or playing a game of cards (strip poker - if she doesn't like that idea you can claim it was a joke).
Speaking of stripping, be aware of what you are (and aren't) wearing around her, with showing off your best features and/or allowing easy access in mind. You might even consider going "naturist" or nudist at home. But in general, women don’t react the same way to nudity as men do to female nudity. And never think that just “whipping it out” or sending her a picture of it will get you anywhere positive. Remember, you need to treat her with respect. Going nude, even just starting in your room with the door open, and no longer hiding your masturbation is about creating an atmosphere of freedom. It might inspire her to do likewise.
Be prepared to appeal to her heart, libido, and intellect. Be prepared to answer whatever concerns to she might have, including assuring her you can keep private things private, that there's nothing wrong with sharing affection if you both want it, and that many other people are doing it. Again, if she resists or indicates she’s not willing, back off! There’s a chance she just needs to think about it for a bit longer, or there’s a chance it won’t go any further, and you have to respect that. Going slowly might help. For example, telling her “Let’s just try kissing, and if you don’t like that, we can stop.”
After the first time together, residue of sex-negative programming might bother her. Reassure her with anything from a smile, to hand-holding, to an embrace, to talking (including thanking her and telling her how much you enjoyed what you’ve just experienced together), to a shower together, to another round of lovemaking. You want to let her know you wanted this and enjoyed it and that there’s nothing to be ashamed or embarrassed about.
Keep in mind that, depending on her age, it would be a good idea to have lube available, and her body might not be able to lubricate enough on its own.
This is generalized. Adjust and adapt as best for you and your relationship with her and life situation.