Editor templates work by convention. The name of the template must match the name of the type. So for example if SomeValue is an int type you could write a custom editor template at ~/Views/Shared/EditorTemplates/Int32.cshtml which will be used. In this case all integer types will use this custom template when you write @Html.EditorFor(model => model.SomeValue).
If you don't want to override all templates for integer types you could write a specific named template ~/Views/Shared/EditorTemplates/Number.cshtml that you could use only for some properties by specifying this template name as second argument to the EditorFor helper: @Html.EditorFor(model => model.SomeValue, "Number") or by decorating your view model property with the [UIHint] attribute:
[UIHint("Number")]
public int SomeValue { get; set; }
and then simply using @Html.EditorFor(model => model.SomeValue) will render the Number.cshtml custom template.
I would also recommend you reading Brad Wilson's blog post about the default templates in ASP.NET MVC.