diff --git a/doc/md/faq.md b/doc/md/faq.md
index eecd3147a..4dd40f8c4 100644
--- a/doc/md/faq.md
+++ b/doc/md/faq.md
@@ -13,7 +13,7 @@ sidebar_label: FAQ
 [How to add custom predicates to the codegen assets?](#how-to-add-custom-predicates-to-the-codegen-assets) \
 [How to define a network address field in PostgreSQL?](#how-to-define-a-network-address-field-in-postgresql) \
 [How to customize time fields to type `DATETIME` in MySQL?](#how-to-customize-time-fields-to-type-datetime-in-mysql) \
-[How do I use a custom generator of IDs?](#how-do-i-use-a-custom-generator-of-ids)
+[How to use a custom generator of IDs?](#how-to-use-a-custom-generator-of-ids)
 
 ## Answers
 
@@ -319,7 +319,7 @@ field.Time("birth_date").
 	}),
 ```
 
-#### How do I use a custom generator of IDs?
+#### How to use a custom generator of IDs?
 
 If you're using a custom ID generator instead of using auto-incrementing IDs in
 your database (e.g. Twitter's [Snowflake](https://github.com/twitter-archive/snowflake/tree/snowflake-2010)),
@@ -341,21 +341,22 @@ type BaseMixin struct {
 	mixin.Schema
 }
 
+// Fields of the Mixin.
 func (BaseMixin) Fields() []ent.Field {
 	return []ent.Field{
 		field.Uint64("id"),
 	}
 }
 
+// Hooks of the Mixin.
 func (BaseMixin) Hooks() []ent.Hook {
 	return []ent.Hook{
 		hook.On(IDHook(), ent.OpCreate),
 	}
 }
 
-var sf = sonyflake.NewSonyflake(sonyflage.Settings{})
-
 func IDHook() ent.Hook {
+    sf := sonyflake.NewSonyflake(sonyflage.Settings{})
 	type IDSetter interface {
 		SetID(uint64)
 	}
diff --git a/doc/md/schema-fields.md b/doc/md/schema-fields.md
index bd13f843c..f19fb054e 100755
--- a/doc/md/schema-fields.md
+++ b/doc/md/schema-fields.md
@@ -149,14 +149,12 @@ to specify a function which will always be ran when the resource is created.
 See the [related FAQ](faq.md#how-do-i-use-a-custom-generator-of-ids) for more information.
 
 ```go
-var globalIDCounter int64 = 0
-
 // Fields of the User.
 func (User) Fields() []ent.Field {
 	return []ent.Field{
 		field.Int64("id").
 			DefaultFunc(func() int64 {
-				// example of a dumb ID generator - use a production-ready alternative instead
+				// An example of a dumb ID generator - use a production-ready alternative instead.
 				return time.Now().Unix() << 8 | atomic.AddInt64(&counter, 1) % 256
 			}),
 	}
@@ -261,8 +259,8 @@ func (User) Fields() []ent.Field {
 }
 ```
 
-In case your `DefaultFunc` is also returning an error, it is better if it is
-handled properly. [See this FAQ.](faq.md#how-do-i-use-a-custom-generator-of-ids)
+In case your `DefaultFunc` is also returning an error, it is better to handle it properly using [schema-hooks](hooks.md#schema-hooks).
+See [this FAQ](faq.md#how-to-use-a-custom-generator-of-ids) for more information. 
 
 ## Validators