Flora and fauna
Birds, lots of them.
By car or bicycle
Drive from Szczecin through Pilchowo and Tanowo; just after Tanowo you will see "Świdwie" sign. After few kilometers of gravel road you'll arrive at small village Węgornik; there you will see another sign. Leave your car on parking, climb the tower (you can't enter the reservation without previous arrangement with its office) and enjoy the view.
There is bicycle path connecting Szczecin (Głębokie) with Pilchowo and Tanowo; you can also ride through the forest by fire roads if you have good map (topographic map preferred) and more rugged bicycle (it's quite flat but expect a lot of sand).
Fees and permits
Entry is free. If you want you can arrange guided tour: http://www.swidwie.pl/
The birds. Take good binoculars and/or lenses for the camera.
Photos of the birds. You can make campfire in designated area, but ask the reservation guard for permission first. Don't shout. Don't scare the animals.
You can't buy anything here. Nearest shop is in Tanowo.
Bring your own food. If you are so inclined you can try collecting mushroom or berries in forest outside reservation area.
Bring your own drink. Drinking alcohol is prohibited at reservation and will incur the wrath of guards.
Sleep in Szczecin. You can try asking people at nearby Węgornik village to pitch a tent, perhaps some will allow you to do it at their premises.