You can join with the groups that depart from Manali to Ladakh as the group has medics, mechanics and guides as well. For Delhi to Manali you can manage through Punjab which has good network of roads and plenty of options to stay, eat and relax.
Dear Manish Just go through this and make your own Itinerary. (i) Leh
1. Hall of Fame Museum 2. Namgyal Tsemo Monastery 3. Leh Palace 4. Zorawar Fort 5. Shanti Stupa ( Buddhist temple ) 6. Shey Palace ( Monastery ) 7. Thiksey ( Monastery ) 8. Hemis Gompa 9. Magnetic Hill 10. Gurudwara Pathar Sahib 11. Khardung La (ii) Nubra Valley
1. Diskit Gompa 2. Hunder Sand Dunes with Camel Safari 3. Turtuk Village 4. Tiger Camp 5. Charasa 6. Ensa Monastery (Gompa) 7. Yarab Tso Lake 8. Panamik Hot Spring (iii) Pangong Lake (iv) Changthang
1. Chushul 2. Hanle with Indian Astronomical Observatory 3. Tso Moriri Lake with wildlife 4. Puga Valley 5. Tso Kar Lake 6. Yaye Tso 7. Chumathang Hot Spring 8. Kiyari war memorial (v) Aryan Valley (vi) Leh to Kargil
1. Nimu village 2. Likir, Alchi, Lamayuru Monastery 3. Fotu La, Namika La 4. Mulbekh Monastery (vii) Suru Valley
1. Parkachik Glacier 2. Nun Kun mountain 3. Rangdum (viii) Zanskar Valley
1. Padum 2. Phuktal Gompa 3. Chadar Trek (ix) Hemis National Park
1. Stok kangri 2. National Park but Main Focus SNOW LEOPARD (x) Leh - Manali Road Trip
*** Leh --> Shey --> Thiksey --> Karu --> Upshi --> Rumtse --> Taglang La --> Debring --> More plains --> Pang --> Lachalung La --> Sarchu --> Suraj Tal --> Baralacha La --> Zing Zing Bar --> Darcha --> Jispa --> Kyelang --> Gondhla --> Khoksar --> Rohtang La --> Kothi --> Manali