diff --git a/dvc_http/__init__.py b/dvc_http/__init__.py
index e68c07c..3f05464 100644
--- a/dvc_http/__init__.py
+++ b/dvc_http/__init__.py
@@ -43,59 +43,56 @@ class HTTPFileSystem(FileSystem):
     SESSION_BACKOFF_FACTOR = 0.1
     REQUEST_TIMEOUT = 60
 
+    def __init__(self, fs=None, timeout=REQUEST_TIMEOUT, **kwargs):
+        super().__init__(fs, **kwargs)
+        self.upload_method = kwargs.get("method", "POST")
+
+        client_kwargs = self.fs_args.setdefault("client_kwargs", {})
+        client_kwargs.update(
+            {
+                "ssl_verify": kwargs.get("ssl_verify"),
+                "read_timeout": kwargs.get("read_timeout", timeout),
+                "connect_timeout": kwargs.get("connect_timeout", timeout),
+                "trust_env": True,  # Allow reading proxy configs from the env
+            }
+        )
+
     def _prepare_credentials(self, **config):
         import aiohttp
 
-        credentials = {}
-        client_kwargs = credentials.setdefault("client_kwargs", {})
-
-        if config.get("auth"):
-            user = config.get("user")
-            password = config.get("password")
-            custom_auth_header = config.get("custom_auth_header")
-
-            if password is None and config.get("ask_password"):
-                password = ask_password(config.get("url"), user or "custom")
-
-            auth_method = config["auth"]
-            if auth_method == "basic":
-                if user is None or password is None:
-                    raise ConfigError(
-                        "HTTP 'basic' authentication require both "
-                        "'user' and 'password'"
-                    )
-
-                client_kwargs["auth"] = aiohttp.BasicAuth(user, password)
-            elif auth_method == "custom":
-                if custom_auth_header is None or password is None:
-                    raise ConfigError(
-                        "HTTP 'custom' authentication require both "
-                        "'custom_auth_header' and 'password'"
-                    )
-                credentials["headers"] = {custom_auth_header: password}
-            else:
-                raise NotImplementedError(
-                    f"Auth method {auth_method!r} is not supported."
-                )
-
-        if "ssl_verify" in config:
-            client_kwargs["ssl_verify"] = config["ssl_verify"]
+        auth_method = config.get("auth")
+        if not auth_method:
+            return {}
 
-        for timeout in ("connect_timeout", "read_timeout"):
-            if timeout in config:
-                client_kwargs[timeout] = config.get(timeout)
+        user = config.get("user")
+        password = config.get("password")
 
-        # Allow reading proxy configurations from the environment.
-        client_kwargs["trust_env"] = True
+        if password is None and config.get("ask_password"):
+            password = ask_password(config.get("url"), user or "custom")
 
-        credentials["get_client"] = self.get_client
-        self.upload_method = config.get("method", "POST")
-        return credentials
-
-    async def get_client(
-        self,
-        **kwargs,
-    ):
+        client_kwargs = {}
+        if auth_method == "basic":
+            if user is None or password is None:
+                raise ConfigError(
+                    "HTTP 'basic' authentication require both "
+                    "'user' and 'password'"
+                )
+            client_kwargs["auth"] = aiohttp.BasicAuth(user, password)
+        elif auth_method == "custom":
+            custom_auth_header = config.get("custom_auth_header")
+            if custom_auth_header is None or password is None:
+                raise ConfigError(
+                    "HTTP 'custom' authentication require both "
+                    "'custom_auth_header' and 'password'"
+                )
+            client_kwargs["headers"] = {custom_auth_header: password}
+        else:
+            raise NotImplementedError(
+                f"Auth method {auth_method!r} is not supported."
+            )
+        return {"client_kwargs": client_kwargs}
+
+    async def get_client(self, **kwargs):
         import aiohttp
         from aiohttp_retry import ExponentialRetry
 
@@ -113,12 +110,12 @@ async def get_client(
         # data blobs. We remove the total timeout, and only limit the time
         # that is spent when connecting to the remote server and waiting
         # for new data portions.
-        connect_timeout = kwargs.pop("connect_timeout", self.REQUEST_TIMEOUT)
+        connect_timeout = kwargs.pop("connect_timeout")
         kwargs["timeout"] = aiohttp.ClientTimeout(
             total=None,
             connect=connect_timeout,
             sock_connect=connect_timeout,
-            sock_read=kwargs.pop("read_timeout", self.REQUEST_TIMEOUT),
+            sock_read=kwargs.pop("read_timeout"),
         )
 
         kwargs["connector"] = aiohttp.TCPConnector(
@@ -136,7 +133,7 @@ def fs(self):
             HTTPFileSystem as _HTTPFileSystem,
         )
 
-        return _HTTPFileSystem(**self.fs_args)
+        return _HTTPFileSystem(get_client=self.get_client, **self.fs_args)
 
     def unstrip_protocol(self, path: str) -> str:
         return path
diff --git a/dvc_http/tests/test_config.py b/dvc_http/tests/test_config.py
index a75fefd..86cd848 100644
--- a/dvc_http/tests/test_config.py
+++ b/dvc_http/tests/test_config.py
@@ -50,7 +50,7 @@ def test_custom_auth_method():
 
     fs = HTTPFileSystem(**config)
 
-    headers = fs.fs_args["headers"]
+    headers = fs.fs_args["client_kwargs"]["headers"]
     assert header in headers
     assert headers[header] == password