Take a train from Delhi to Pathankot. From Pathankot take a bus to Dharamshala bus stand. Take a local bus from here to Macleodganj bus stand as a taxi will cost you more. From there take an auto to Bhagsu(Rs50 per auto).
Make a prebooking either with OYO or MMT.
Leave Bhagsu early morning for paragliding. You have to go to Bir and Billing(Palampur). It will take approx 4 hours. It is the world's 2nd highest point for paragliding. Cost per person is 2k-4k depending on the tourist season.
1)Take a taxi and go to Gallu Devi temple-from where the actual trek begins.
2)Via Dharamkot: Go to Dharamkot from Bhagsu by walk or taxi. The main thing in Dharamkot is wooden pizza(Must give a try).
From dharamkot, it is a 2KM hike to reach Gallu Devi temple from where the actual trek begins.
3)Via shiva cafe-this route is not well marked and very less opted by trekkers.
Don't do any prebooking for Triund trek. The trails are well marked so no need of any guide and you can get camps at Rs500 per person at the top.