* Validation is important for everyone, but especially for people on the asexual spectrum who often get ignored or contradicted. Know the levels and methods of validation.
* When you hear someone say rude or inaccurate things about the asexual spectrum, interrupt and correct them. Be an upstander.
* At social events, buffer for your acespec friends if they appreciate that. There can be a lot of pressure to dance, drink, pair up, talk about sex/romance, or other things they just don't want to do. Often people will tease them about being single. Quash all of that and let people know that you don't appreciate it. Acefolk can do this too, but they have to do it over and over again, which is exhausting. This makes social events suck, which is the opposite of helpful.
* If you throw an introvert party, invite your acespec friends. (See a description of an introvert party.) They are more likely to enjoy a quieter event without the heavy-duty socializing that so often leads to people making passes at each other. Keep a supply of solo games or other quiet activities that people can dig into, and preferably a quiet corner or room, at busier parties too.
* Accept uncertainty. Human sexuality (or the lack thereof) can be confusing and ambiguous. That's okay. People who identify as aceflux, arovague, graysexual, questioning, etc. will appreciate a chance to be who they are without pressure to pin it down. Explore ways to embrace uncertainty. Play games of chance, games with changing rules, games with flexible interpretations, or creative games. You can't beat 1000 Blank White Cards for versatility. Loose parts play can be fun for all ages.
* Some demisexual and/or demiromantic people like to take things slow in general. You can help by being patient, letting them set the pace, and looking for leisurely things you all enjoy. Consider slow food, slow TV, and slow crafts. Birdfeeder videos can be very relaxing. Walking and/or biking instead of driving encourage mindfulness.
* Many acespec folks have a passion, something that interests them as much as sex/romance interests other people. It might be their job, a hobby, a worthy cause, or something else. If you have close friends who are ace, find out what they love and ask them about it as often as people talk about sex/romance with other friends. Many aces feel like a "third wheel' in society, but asexuality/aromance has definite advantages like having more time and energy or being less distractable due to sex/romance. Encourage people to appreciate those.
* Try to find entertainment that doesn't rely heavily on sex/romance. It's boring to watch a movie when only half of its plot is something you understand or care about. It's frustrating to attend events where most or all of the decorations, conversations, and activities focus on things that bore or annoy you. Gentle fiction has no sex, violence, or foul language; gentle cinema is similar. Some events such as parades focus much less on couples than events like dances do -- although there are line or circle dances without a couple format.
* Some acespec people are tractive -- interested in close, long-term relationships -- and others aren't. Asexual-romantic people often want to find a romantic partner. Asexual-aromantic people sometimes want to find a queerplatonic partner. Pay attention to your circle of friends, and if you notice that certain people seem to be compatible, introduce them to each other. It can be very hard for acefolk to find each other in a sexual society, and few people help. You don't have to play matchmaker, or say anything about their orientation (unless they're both out and actively looking for a partner), just introduce them like you would any other friends.
* Loneliness ruins physical and mental health, and it can be fatal. Because society expects people to pair up, acespec people face a higher risk of loneliness and often fear it. Watch for signs that someone is lonely or needs a friend, and reach out to them. Cooperative games can help people feel included.
* Skin hunger is another big risk, and America has a taboo against wanting touch even though humans need it to survive. Society tends to assume that people get touch through sex/romance, but not everyone wants that, and finding platonic touch can be very difficult. Here are some ways to cope with skin hunger. If you enjoy platonic touch with friends, let your acespec friends know that and assure them you won't ask for sex/romance. Some party games involve touching.
* Practice emotional intimacy. It deepens relationships and helps people feel connected. Ask deep questions. (Be aware that for some people -- demisexuals, demiromantics, asexual romantics, etc. -- this can constitute heavy foreplay.) People need connections to each other in order to thrive, which can be difficult for folks who don't connect through sex/romance.