If you don’t know much about the God you want to worship, start with research, read and learn about them more. (Always a good place to study about the Netjeru is Henadology website.)
After learning more about the Deity, you can start worship. It’s not required to do any formal rituals of “introducing yourself”, however there are examples of such rituals if you feel so inclined.
You may start simply with a short prayer and offering. Or just with prayer, as prayers always is more important than material offerings.
You may start offerings with candles and incense, later offer something edible. It’s never wrong to offer Netjeru water, bread, fruits and sweets.
Kemetic offerings are usually “reverted” after some time of being presented to the Netjeru. So, offer the things you will like to consume yourself, later!
And if you already reached the God/s and established the devotional relationship - then work on this devotion more than on the offerings.
Show them your love. Think about them. Repeat their names in your mind. Say them praise. Study about them. Use the opportunities to see more of their pictures and read more about their mythology, cult, ways of worship. Contact other devotees of that God and see their experiences.
But before all, IMHO, is thinking about the God/s, keeping them in your mind, let them make a shrine in your heart.
They welcome our love and devotion more than material offerings. Material offerings are more for us than for Them, because they help us to keep our attention focused and concentrated.
The same thing is with holy images and statues. You may look at the pictures of the God on line, you may make a home shrine, but most important is to welcome them into your life and your heart.
Because what else was your goal in connecting to individual God?
You want to be their friend, perhaps. And yes, this means that they would influence your life. This does not happen in one moment. But you may find eventually that you start changing “in the likeness of the God”. Their values become your values. Their goals and agendas become yours. You start to love what they love, and reject what they reject. You think about them more and more, you wake up with first thought of saying hello to the God.