diff --git a/src/append_to_group.ts b/src/append_to_group.ts
index 1848a0d..158fd1b 100644
--- a/src/append_to_group.ts
+++ b/src/append_to_group.ts
@@ -1,8 +1,12 @@
-import { Redmine } from 'bluemine';
-import { CsvEntry } from '../type.ts';
-import { toLogin } from '../utils.ts';
+import { Redmine } from 'bluemine'
+import { CsvEntry } from '../type.ts'
+import { log, toLogin } from '../utils.ts'
 
-async function addUsersToGroup(redmine: Redmine, csv: CsvEntry[]) {
+async function addUsersToGroup(
+	redmine: Redmine,
+	csv: CsvEntry[],
+	groupName: string,
+) {
 	const users: Redmine['users']['List']['Result']['users'] = []
 
 	for (const { firstname, lastname } of csv) {
@@ -12,10 +16,11 @@ async function addUsersToGroup(redmine: Redmine, csv: CsvEntry[]) {
 			const list = await redmine.users.list({ limit: 1, name: login })
 			const user = list.users[0]
 
-			console.log(`get user: ${user.login}#${user.id}`)
+			log.info(`get id of ${user.login}#${user.id}`)
 			users.push(user)
-		} catch {
-			console.error(`error list: ${login}`)
+		} catch (error) {
+			log.error(`get id of ${login}`)
+			console.error(String(error))
 		}
 	}
 
@@ -25,10 +30,10 @@ async function addUsersToGroup(redmine: Redmine, csv: CsvEntry[]) {
 
 	for (const user of users) {
 		try {
-			console.error(`ok: ${user.login}#${user.id}`)
+			log.info(`add ${user.login}#${user.id} to "${groupName}"`)
 			await redmine.unstableGroups.addUser(id, user)
 		} catch {
-			console.error(`error: ${user.login}`)
+			log.error(`add ${user.login}#${user.id} to "${groupName}"`)
 		}
 	}
 }
diff --git a/src/create_users.ts b/src/create_users.ts
index c6b7cf6..3e0a662 100644
--- a/src/create_users.ts
+++ b/src/create_users.ts
@@ -1,8 +1,12 @@
 import { Redmine } from 'bluemine'
 import { CsvEntry } from '../type.ts'
-import { capitalize, sanitize, toLogin } from '../utils.ts'
+import { capitalize, log, sanitize, toLogin } from '../utils.ts'
 
-async function createUsers(redmine: Redmine, csv: CsvEntry[]) {
+async function createUsers(
+	redmine: Redmine,
+	csv: CsvEntry[],
+	groupName: string,
+) {
 	const userIds: number[] = []
 
 	for (const { firstname, lastname, mail } of csv) {
@@ -18,11 +22,22 @@ async function createUsers(redmine: Redmine, csv: CsvEntry[]) {
 				generatePassword: true,
 			})
 
+			log.info(`create user ${login}#${user.id}`)
 			userIds.push(user.id)
-		} catch {
-			console.error(login)
+		} catch (error) {
+			log.error(`create user ${login}`)
+			console.error(error)
 		}
 	}
 
-	await redmine.unstableGroups.create({ name: 'entrepreneur-01-24', userIds })
+	try {
+		log.info(`add to "${groupName}" users [${userIds.join(', ')}]`)
+		await redmine.unstableGroups.create({
+			name: 'entrepreneur-01-24',
+			userIds,
+		})
+	} catch (error) {
+		log.error(`add to "${groupName}" users [${userIds.join(', ')}]`)
+		console.error(error)
+	}
 }
diff --git a/utils.ts b/utils.ts
index 50c8293..a79839d 100644
--- a/utils.ts
+++ b/utils.ts
@@ -1,15 +1,36 @@
 export function sanitize(str: string): string {
-    return str.replaceAll(' ', '_')
+	return str.replaceAll(' ', '_')
 }
 
 export function capitalize(str: string): string {
-    return str
-        .split(' ')
-        .map(word => word.split(''))
-        .map(([firstLetter, ...tail]) => `${firstLetter.toLocaleUpperCase()}${tail.join().toLocaleLowerCase()}`)
-        .join(' ')
+	return str
+		.split(' ')
+		.map((word) => word.split(''))
+		.map(([firstLetter, ...tail]) =>
+			`${firstLetter.toLocaleUpperCase()}${tail.join().toLocaleLowerCase()}`
+		)
+		.join(' ')
 }
 
 export function toLogin(firstname: string, lastname: string): string {
-    return `${sanitize(firstname.toLocaleLowerCase())}.${sanitize(lastname.toLocaleLowerCase())}`
+	return `${sanitize(firstname.toLocaleLowerCase())}.${
+		sanitize(lastname.toLocaleLowerCase())
+	}`
+}
+
+export const log = {
+	info(message: string) {
+		console.log(
+			`%c[info]%c ${message}`,
+			'color: cyan; font-weight: bold',
+			'color: white',
+		)
+	},
+	error(message: string) {
+		console.error(
+			`%c[error]%c ${message}`,
+			'color: red; font-weight: bold',
+			'color: white',
+		)
+	},
 }