Adding new model to existing ones using Code First

Currently I achieve the above as follows.

Question: Is it the right approach in order to keep the data in the exiting tables in tact. I feel I'm doing it rather a long-winded way. Any suggestions or alternate/correct ways of doing it?

1. Create a new entity (model) and a corresponding DbSet<...> entry in myProjectContext.cs file
2. Delete existing migration from VS2015 and corresponding __EFMigrationsHistory table from the SQL Server Db
3. Run PM> add-migration mytMigration -context myProjectContext
4. Comment out all the code in newly generated mytMigration.cs file except the code related to newly generated entity (model).
5. Run PM> update-database -context myProjectContext

New table (corresponding to newly added entity) gets created in the exiting Db along with new __EFMigrationsHistory table. Data in all the existing tables remains in tact.

UPDATE:

I'm following this official ASP.NET tutorial and - per their advice - have registered our context with dependency injection as follows:

Startup.cs:

public void ConfigureServices(IServiceCollection services)
        {
            var connection = @"Server=myDevMachine\SQL2012Instance;Database=myDb;Trusted_Connection=True;";
            services.AddDbContext<ABCTestContext>(options => options.UseSqlServer(connection));
...
...
}