I want to help in moderation of this page. How can I be moderator ? I have experience in this.
As Ambo100 states, the best way to help is to use the site - as we say in the FAQ:
At the high end of this reputation spectrum there is little difference between users with high reputation and ♦ moderators. That is very much intentional. We don’t run LEGO® Answers - Stack Exchange. The community does.
While we are still in beta, the reputation requirements to access the tools is significantly lower than on a fully fledged site.
That said, we are only "Pro-Tempore" moderators - a few users were invited to be mods while the site was in beta to help nurture and grow the site, when we graduate we will hold full elections, at which point members of the community will be able to volunteer, hustings will be held, votes counted, and so on.
Note that often the criteria for standing in the elections include those traits listed in A Theory of Moderation.
You might also want to check out the following post on Meta.SO as well:
I also had a similar response when we moved from private to public beta ;)
Becoming a diamond moderator is rather hard. Once this site graduates, there will be periodic elections and you can take part in those. Of course, you need to have good standing with the community to have any chance of winning :)
However, if your aim is just to help moderate the site, then that's pretty easy. There are many, many ways to help out (and the more reputation you get, the more you can help since you get additional tools)
I wrote this guide as a one-stop tutorial about the various aspects of community moderation on Physics.SE. Yep, it's long, but not all of it applies to you. There are a few site-specific things there, though, like the bit about the homework policy. The rest pretty much applies just as well to bricks.SE
This FAQ entry, on the other hand, also teaches these aspects, and is site-agnostic. You may find that more helpful :)
Users gain certain privileges with an increase in reputation. At your current reputation, you have the ability to flag posts, flagged posts are handled by users with access to moderation tools, ♦ Community Moderators and Stack Exchange Employees.
With the amount of flags we get per day, the flag queue is very manageable.
The most powerful way for regular users and moderators alike to make a difference, is to: comment, vote, ask, answer, edit and improve posts.