When you find a host who you are interested in, why don't you send him/her a message?
I normally make a travel plan in advance so I make a contact with hosts at least 4weeks before than my plan. I highly recommend you to ask the host about the place in advance so they could also make a plan.
Here, the things that I mention on my first email;
1. Name
2. Nationality
3. How long have I been the country
4. Current location
5. Next destination and travel plan (when and how long will I be)
6. The reasons why I am interested in visiting the host
E.X
Dear ****
Hello, this is Manami Togami from Japan. I have been traveling
Tasmania as a Helpx helper and I have worked for 3 hosts since December. I have
been having a nice time with the hosts, the other helpers and the locals who I
have met here. I am going to visit two more Helpx hosts (Host ID: *****, ****)
in Tasmania until the middle of May. After that I am planning to visit Melbourne
area. So, I am willing to work at your place for 4-5 weeks if it is suitable for
you. I would like to visit you because I have read the reviews and I really like
what the helpers explained about you all. I am interested in meeting new people
and I have met so many wonderful helpx hosts in Australia. I am hoping to expand
a good relationship with people in Australia and have a new experience. Please
check my profile and I am looking forward to hearing from you!
Best Regards,
Manami Togami
You want to know the details about the hosts so same as the hosts, they also want to know about you! If you want attract their interests of having you, you need to make a message personal, Not copy and paste as helpx tips said!!