Well, firstly it's important to know that Utsuho is an incredible powerhouse, once you get over her icredibly slow attack speed. You'll definitely have a hard time playing her as any other character if you try to rack up fierce combos and are used to swiftly linking physical attacks. to be quite fair, Utsuho is definitely not a comboing character, but she can definitely stand her ground along the ranks of long-flight, long-distaznce hard hitters such as Reimu or Iku. From my experience, your main moves should be 3A - 3C or Acont - 421B/C.Personally I've found Utsuho's alternative decks to prove much more reliable in terms of combos, but make sure you don't throw out 421.
Where Utsuho does get the good stuff is her specials and spellcards. 236B is perfect for clearing out a giant field of bullets, 22C can easily take down charging attacks like Sakuya's Killing Doll, and CPU opponents are rigged in such a way that a decently aimed fixed star will ALWAYS connect.
If you need any more info after this, Utsuho probably isn't for you. But still if you insist, go check the wiki for more advanced combos.