What are your Travel dates and point of Origin? Any Specific thing on mind and mode of transport preferred? Start from a day or two at Ahmedabad which is also a part of North - Central Gujarat which is mix of Temples, History and Architecture the major sights are Modhera Sun Temple, Rani Ki Vav Patan,Patan Patola Heritage, Patan City Museum, Panchasara Jain Temple, Ambaji Shaktipeeth Temple & Gabbar Hill, Idar Hills, Poshina, Polo Forest & Vijaynagar, Temples at Mahesana etc. South Central Gujarat has many things to offer starting from the Sanskari Nagari of Vadodara, Champaner Pavagadh Heritage Complex, Pavagadh Mahakali Temple, Statue of Unity, Dandi Memorial near Navsari, Dumas Beach and Textile / Diamond Markets in Surat, Nilkanth Dham Temple at Poicha, Kuber Bhandari Temple and Narmada River boat Ride, etc. Further if you are intrested than you may dig deeper into Dan /Ahwa the Maharashtra border district of Gujarat.
Coming to Saurasthtra you will need a lot of time here as it is packed with Hills & Mountains, Beaches and Temples, Forts and Musuems and Gir National Park like cherry on the top. Start from Velavadar Black buck National park near Bhavnagar followed by high hill Jain Temples of Palitana, Diu, Gir National park, Somnath, Junagadh & Girnar, Porbandar, Dwarka, Jamnagar, Rajkot, etc. By now you will be like a half gujju I guess and so it's time to dive into the Ocean of Variety at Kutch Region which has all elements including Beaches, Hills / Mountains, Forts, Musuems, Temples, Gardens, Harappan Site, etc. Start with Bhuj town followed by Day trips to White Desert known as Great Rann of Kachchh, Black Hills, Khavda Village, etc. Then comes the beach town of Mandvi offering Vijay Vilas palace (featured in few bollywood movies), Beach, Kranti teerth Shyamji Krishna Verma memorial, Jain temples, etc. Now roll on towards western most tip of the country at Lakhpat, Narayan Sarovar, Koteshwar temples, Nirona Village for local art, etc. Finally know the existence of Harappan Civilization at Dholavira and Fossil Park ahead of it. Kutch Region can be completed in 3 to 4 days, whereas all other zones require minimum 5 to 6 days. Further if origin point, dates and mode of transport are known then can help you draw a rough itinerary till then Jay Shri Krishna Bhai (as they say in Gujarat).