diff --git a/lexicon.md b/lexicon.md
new file mode 100644
index 0000000..482dbaa
--- /dev/null
+++ b/lexicon.md
@@ -0,0 +1,54 @@
+https://resolve-lexicon.pages.dev/
+
+例えば、`ai.syui.log.post`を作りたいとして、まずは、`syui.ai`にdnsを追加します。
+
+```sh
+_lexicon.log.syui.ai  TXT  "did=did:plc:uqzpqmrjnptsxezjx4xuh2mn"
+```
+
+次に、schemeを`did:plc:uqzpqmrjnptsxezjx4xuh2mn`にputします。
+
+> at://did:plc:uqzpqmrjnptsxezjx4xuh2mn/com.atproto.lexicon.schema/ai.syui.log.post
+
+```json
+{
+	"repo": "did:plc:uqzpqmrjnptsxezjx4xuh2mn",
+		"collection": "com.atproto.lexicon.schema",
+		"rkey": "ai.syui.log.post",
+		"record": {
+			"$type": "com.atproto.lexicon.schema",
+			"lexicon": 1,
+			"id": "ai.syui.log.post",
+			"defs": {
+				"main": {
+					"type": "record",
+					"key": "tid",
+					"description": "Record containing a blog post.",
+					"record": {
+						"type": "object",
+						"required": ["title", "content", "createdAt"],
+						"properties": {
+							"title": { "type": "string", "maxLength": 3000, "maxGraphemes": 300 },
+							"content": { "type": "string", "maxLength": 1000000, "maxGraphemes": 100000 },
+							"createdAt": { "type": "string", "format": "datetime" },
+							"lang": { "type": "string", "maxLength": 10 },
+							"translations": { "type": "unknown" }
+						}
+					}
+				}
+			}
+		}
+}
+```
+
+```sh
+$ curl -X POST "https://bsky.syu.is/xrpc/com.atproto.repo.putRecord" \
+  -H "Authorization: Bearer $TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "repo": "did:plc:uqzpqmrjnptsxezjx4xuh2mn",
+    "collection": "com.atproto.lexicon.schema",
+    "rkey": "ai.syui.log.post",
+    "record": { ... }
+  }'
+```
\ No newline at end of file