and prefer to send an email. I can tailor my request without leaving blanks in a form.

In the old days,  I would send a PM from my main TER handle so that she can see my whitelist.  

If she has a listed phone number I may send a very brief text alerting her of the email or PM.

I'll certainly give 24 hours, maybe more for a response,  and will always reply back that I received it, whether we set up an appointment or not,  just to be polite and close the loop.

I almost always make my first contact with a provider who is new to me by text. I’ll send an introduction with my age, race, retired status, and reference to my TER handle and whitelists and ask for an appointment during a time window. If I don’t receive a response within 4-6 hours I move on to another provider. I don’t recall ever making first contact through a provider’s website, and the only time I’ve used email is where the provider doesn’t have a phone number in her ad or  TER profile.

... I would prefer to get same-day responses. But I consider it acceptable to wait up to 3 days for a reply.  Checking spam folders is (or should) be a regular-daily activity for anyone using email to communicate.  

 
If I am looking to book in a shorter time span than 3-4 days, I will send a text with date/time, name, email and some context-appropriate screening info like TER ID or P411.  I generally do not like to use web forms as my experience is a high  no-reply rate within 3 days.  

 
One reason you may see guys not reply to your reply may come a common practice of sending messages to multiple providers at the same time. Many guys will generally book the 1st provider who replies and ignore the rest.  Sadly, if you respond after someone else did, you may never know why he ghosted you. Why do this? If the guy has a tight schedule and little flexibility for changes, he may want to ensure he gets a session booked. If he waits for one to reply (up to 3 days) before moving on to the next, he may just run out of time to get the day and time booked that he wants.  In my opinion, he should respond to the replies received later that he already booked with someone else as a courtesy. But my guess is many don't bother.  

 
Life is good

 
The Cat

then I prefer to use that channel. That way, the provider has easy access to my OKs and my profile, which should be useful for screening.  

 
Your advice re checking spam folders is good, for both guys and gals.  

Well, almost never.

My order of contact sequence goes something like this.

After I research a provider on P411 and TER, I will reach out via P411 PM if she frequents the website daily.  If not, I send an e-mail with the basic information.  Once I get a response I will share my P411 ID for verification, as I do not visit ladies who are not on P411.

Once in a great while, and usually on request of the provider, will I fill out a web site from.  

Depending how far I book out I can wait up to three days for a response.

I hope that helps.

Email all day every day.

Email

I normally email because the forms always ask for a date/time.  But, I may not have one yet.  I always reach out to be verified beforehand.  Also forms can be tough, never know if they actually work or it's going to spam. etc.  If I email I wait 1-3 days.  If there's no response I assume there's an issue.  But, 99% of the time I get a reply within 24 hours.

I HATE HATE HATE booking forms

They're impersonal.  They're too transactional.  They don't allow for adjustments.  And in my experience, they never answer.  And worst, they demand information that you end up not knowing what happens with it.  

This is an industry of trust, personal connection and chemistry.  I'm always looking to become a regular, not a one shot deal.  For me, it's a bad way to start.

I even prefer assistants.......

Seriously if a mention of P-411 to her direct email or PM sent does not open the door to more serious talks I start looking  
for other options. With that being said I plan several days in advance to let these things work out.  
Put my private info on a some vague form on a website I would pass.  

Forms? Never again

Just tried using a form on a provider's site since a long time ago. Never received a response, and have no idea what happened to it.  
From now on I will use only email or text.

Especially given that many ask for information I would never divulge (e.g. work information or full name).

I send a polite and short email in which I enquire about available times and offer references.  

If that's not acceptable, or if there's no reply in 24 hours, I move on.

If the provider is a member of TER, I prefer sending her a pm through TER, that way she can see my profile and reviews of providers I have seen, otherwise I will send her a email with my first name, age, race, occupation date and time I want to meet along with 2 references and I always give her plenty of time to respond( usually 3 to 4 days) because I do realize some providers have another life outside of the hobby!