Twitter is good for hot and trending topics. Show that you offer something and use relevant hashtags. The good thing about hashtags is that people are always checking them out. Here you can directly link them to your website.

what about using twitter search for lead generation , i am thinking to create an app for my use to notify me when someone right some phrases for example (wordpress Developer ,PHP error ).
Se even i will automate a reply or to manually check the tweet and reply and offer him a service like fiverr gigs

It is another good point.
The fact for any kind of marketing is making profit and this only be generated by precisely targeting leads, not general leads. Can you PM me how are you planning to do it? We may share more for even better success

The biggest difference I notice about Twitter compared to other social media platforms, is Twitter seems to be mostly automated. Any program that helps people build their account without having to be there (macro) would be useful. I agree with the #Hashtag idea others have stated as well. Twitter is all about "trending #Hashtags" so if you could find a way to capitalize on that people would most likely be interested.

I agree with you that automated posts have been overloading twitter since long ago. But still there is catch, few people comparing to vast usebase of twitter are using automated software. Most users are real, manually using twitter for their own purpose.

I think, the best practice would be to entice them, add them into our network and connect. We can make our real prospect from this platform just by engaging.

Define your business goals and objectives,take something you want to accomplish in your business and break it down into action items that are measurable and specific.When you’re starting out in social media, it’s best to focus your objectives on something you can control: your behavior Create your conversation strategy, people will follow you if you talk about things that interest them. Of course, you can talk about your business, offer discounts and exclusive specials, share practical tips and announce your business products and services. Organize your community with Twitter Lists Create your lists and organize your current Twitter community. Add each new person you follow to the appropriate list when you follow them. Keep expanding your Twitter community, It’s important that you don’t follow too many new people at one time. Twitter spammers aggressively follow a large number of people in short bursts.